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Top 10 differences between a Windows Service and a regular application

What's the difference between an application and a service?

First, let’s start with some definitions…

What is a regular application?

A regular application is one that you start and run on your Windows desktop. You launch it from a desktop icon, by double-clicking an associated document, or by typing its name at a command prompt. Examples include Microsoft Excel, Adobe Reader, Google Chrome and virtually any other program you consciously interact with on your PC. These are the programs that you know, love and use every day — the ones that make your computer a remarkably powerful tool.

What is a windows service?

A Windows Service is a special program designed to “plug into” Windows. It typically chugs along doing its work in the background, never revealing itself, with little or no attention from anyone using the PC. It turns out that a whole host of these invisible workers are necessary to make your PC work smoothly! For example, the Print Spooler windows service ensures that your documents arrive at the printer, while the Workstation service makes the Internet available for all applications. Important tasks indeed!

What’s the difference?

So with those basics in place, here are the 10 most important ways that a windows service differs from a regular application:

  1. A windows service can start automatically at boot, without anyone having to log on. A regular application only runs when a user is logged in. This key distinction makes the windows service framework the better choice for software that must run 24×7, surviving the inevitable reboot along the way.

  2. A windows service won’t exit when you or anyone else logs off the PC. A regular application will stop when you log out.

  3. Windows services don’t run visibly on your desktop (not since Vista). They are confined to the isolated Session 0 and can not (usually) show their windows or tray icons to anyone logging into the PC. This restriction makes it very difficult for a windows service to interact with someone using the computer and consequently Microsoft strongly discourages implementing GUI services.

  4. A windows service can be easily started or stopped from the command line using the NET or SC commands. This capability is a boon to sysadmins and technical folks, who can conveniently manage a service’s lifetime through unattended, administrative scripts.

    Starting/stopping a service with the NET Command

  5. Only a single instance of a windows service can be started at any time. That single copy must serve all users on the PC. This is very different than a regular application, which typically permits multiple copies, especially when several people are logged in.

  6. Services typically run in the Local System account, which has administrative powers over many aspects of the PC. Thus your average service will have more rights and control over your computer than your typical application running in the context of a regular user’s account.

    Services Log On tab

  7. When run as LocalSystem, a service has access to UNC paths (for example, “\\server\data”) but cannot access mapped drive letters. You should run the service in a regular user account to access network drives, and even then the service may have to map drives explicitly (for example, with the NET USE command) to gain access.

  8. All windows services support sophisticated recovery options for when they stop unexpectedly. You can restart the service, run a command line or even reboot the computer.

    Windows Service Recovery Tab

  9. While each regular application is backed by a single, unique process, it is possible for many services to share a single running process. This situation makes it possible for some services to start rapidly and make efficient use of resources — important characteristics for critical components that must always be available.

  10. A windows service must contain special code to respond to instructions from the Windows Service Control Manager (SCM). For the technical folks, this means implementing the ServiceMain (or equivalent) entry point in your application.

Posted in Windows Services | Tagged , , , | 1 Comment

How to Setup Email from AlwaysUp

Overview


Email from AlwaysUp

AlwaysUp is designed to run your application as a Windows Service and automatically restart it when it crashes or stops for any reason. Even though this frees you from having to take any action on a failure (eliminating those unwelcome “server-not-working” calls at 3 AM), you may still want to:

  • Find out how often your application is failing
  • Know the time when your program stops working (for diagnostic purposes)
  • See how your application is using CPU and memory over the course of the day
  • Find out whenever your server has been rebooted

Automatic email from AlwaysUp will tell you all that, and more!

Specifying Who to Email & When to Send a Message

To setup email in AlwaysUp, edit your application and switch to the Email tab:


AlwaysUp Email Tab

Enter the following:

  1. The email address to notify. To send to multiple addresses, just separate each one with a comma (,).
  2. When AlwaysUp should send you an email — either in response to an important event, or at a regular time. The daily and weekly summary emails are a good way to monitor your application’s activities without having to receive multiple emails throughout the day.
  3. A line of text to be included in the email. This value is optional, but you can use it to explicitly label a server & application when you have many installed with the same name (for example, when you are running the same application on many different workstations).

Server/SMTP Settings

AlwaysUp doesn’t require that you have Outlook or any other email software installed. Instead, it deals directly with your SMTP server – the machine actually responsible for routing your email over the Internet and delivering it to your recipients. Every major provider (such as Gmail, Yahoo and Office 365) supports SMTP mail and it is simply a matter of providing those settings to AlwaysUp so that it can send messages on your behalf.

Click the Configure… button to reveal the details:


Configure Server Settings

The Configure Email Settings window that comes up requests quite a bit of information, but don’t be scared! Your systems administrator will be able to fill this in while balancing a bowl of water on his head and dancing the Macarena, but in case you are entering these values yourself here is what each field means:


Configure Server Settings

  • Address: The email address that will be displayed in the “From” field of the email messages sent by AlwaysUp.
  • Name: The name that will be displayed in the “From” field of the email messages sent. This value is optional.
  • Name/IP: The name (or IP address) of your mail server.
  • Port: The numeric port on which the mail server is available. Note that the default is 25 for regular SMTP servers and 465 for servers using SSL – please specify one if these if in doubt.
  • This server requires encryption: Check and make the appropriate selection if the mail server uses TLS, SSL or STARTTLS.
  • This server requires authentication: Check if the server requires authentication, and select the authentication method. The choices are CRAM-MD5, AUTH-LOGIN, AUTH-PLAIN, and AUTH-NTLM. A login and a password will be required for all but AUTH-NTLM.
  • Login: The user name/login for the mail server. Usually your full email address.
  • Password: The password for your email account.

 

Gmail
How to use your Gmail Account

To send email with your Gmail account, please specify the following settings:

Address:Your full gmail address (your-user-name@gmail.com)
Name:Your name
SMTP Server Name/IP:smtp.gmail.com
Port:465
Encryption:SSL/TLS
Authentication:AUTH-LOGIN
Login:Your full gmail address (your-user-name@gmail.com)
PasswordYour gmail password

So for someone named Mike Jones, whose Gmail address is jones1985@gmail.com, the Configure Email window should look something like this:

Using Gmail in AlwaysUp

This short, step-by-step video highlights the settings to enter for Gmail:

Note: If your Gmail account uses 2-Step Verification, you will have to create an app password to send email from AlwaysUp.

If not, you may get an error like this when you try to send a test email from AlwaysUp:

Gmail 2-Factor Authentication Error

 

Microsoft Office 365
How to use your Microsoft Office 365 Account

If you have an Office 365 mail account, please specify the settings described here:

Address:Your full Office 365 email address
Name:Your name
SMTP Server Name/IP:smtp.office365.com
Port:587
Encryption:STARTTLS
Authentication:AUTH-LOGIN
Login:Your full Office 365 email address
PasswordYour Office 365 password

So for Mike Jones, whose Office 365 email address is mike.jones@somecompany.com, the Configure Email window should look something like this:


Using Office 365 in AlwaysUp

Note: Because of changes to Office 365 authentication methods, attempts to send email with Office 365 may fail with this message: “Authentication unsuccessful, basic authentication is disabled”.

To overcome that problem, we recommend creating an app password for sending email using office365.com.

 

SMTP2GO
Create a Free Account with SMTP2GO

If you don’t want to (or can’t) use an existing email address, we recommend creating a free account at SMTP2GO. Their free plan will allow AlwaysUp to send you up to 1,000 emails per month.

Address:Your SMTP2GO email address
Name:Your name
SMTP Server Name/IP:mail.smtp2go.com
Port:2525 (or 465, 80, 25, 8025 or 587 if that doesn’t work)
Encryption:SSL/TLS
Authentication:AUTH-LOGIN
Login:Your SMTP2GO email address
PasswordYour SMTP2GO password

Please consult SMTP2GO’s setup guide if you run into trouble with those settings.

Using Another Email Service

This list documents SMTP settings for many other email providers.

 

So that’s it! Please be sure to get in touch if you have any trouble setting up automatic email from AlwaysUp.

Posted in AlwaysUp | Tagged , , , , , , | 4 Comments

Investigate Crashes & Memory Leaks in your Windows Services with Microsoft’s Debug Diagnostic Tool

Microsoft Debug Diagnostic Tool

Crashes and memory leaks are particularly offensive when the occur in windows services – applications designed to run unattended, 24/7 in the background to perform important tasks. Our AlwaysUp and Service Protector utilities go a long way to diminishing the effect of these insidious failures, but using them is no substitute for finding and fixing a problem at its root.

Developers looking to diagnose failures in their windows services should consider using Microsoft’s Debug Diagnostic Tool. This free desktop application, nicknamed DebugDiag, will monitor your windows service process and create a “dump” describing the state of the application when it crashed (or started using too much memory). You can use this information to narrow down the problem in your own code, or pass it on to the folks who developed the failing service for their expert analysis.

Using the Debug Diagnostic Tool on your Windows Service

  1. Download the Debug Diagnostic Tool from microsoft.com.

  2. Install it. Setup should be quite straightforward, with the usual prompts for a folder, etc.

  3. From Windows Explorer, navigate to the folder where DebugDiag was installed (C:\Program Files\DebugDiag by default). Start DebugDiag.Collection.exe – the application that monitors and collects information from a running process or service.


    Start DebugDiag.Collection.exe

  4. The Debug Diagnostic Tool window should come up and you will be launched immediately into setting up a new “rule” describing what to watch for. From here, you can specify to monitor for crashes, leaks, and even performance-related issues. We’ll select Crash for this tutorial and click Next to move on.


    DebugDiag: Select Crash Option

  5. Next, select the A Specific NT service option:


    DebugDiag: Select Windows Service Option

  6. Select the service you wish to debug from the list. We chose “AA MyService”, a windows service we developed to test our Service Protector application. Click Next.


    DebugDiag: Select Windows Service

  7. Almost there! Leave the Advanced Configuration settings at their default values and click Next to continue:


    DebugDiag: Windows Service Advanced Configuration

  8. You don’t have to make any changes on the Select Dump Location screen either – just make a note of where the dump file will be saved.


    DebugDiag: Windows Service Dump Location

  9. And finally, let’s activate the rule now and click Finish:


    DebugDiag: Activate Now

    After a few seconds, the tool will be monitoring your windows service for crashes:


    DebugDiag: Windows Service Rule Created

Analyzing a Windows Service Crash

When the service crashes, DebugDiag will record a dump file and increment the Userdump count column. Here we can see that 1 crash has occurred and been captured (with the full path to the dump file noted on the right):


DebugDiag: Windows Service Crashed

To dig into the dump file:

  1. Start DebugDiag.Analysis.exe from Windows Explorer:


    Start DebugDiag.Analysis.exe

    The DebugDiag Analysis window will open momentarily:


    DebugDiag Analysis Started

  2. To configure analysis:

    1. Check the CrashHangAnalysis box near to the top.
    2. Click the Add Data Files button, navigate to the location of the dump file (it is mentioned in the Diagnostic tool we set up previously) and select it. A new entry should show up in the lower pane.


    Configure Analysis

  3. And click the Start Analysis button to get going! After a period of “thinking”, the application will open its report in your browser:


    Analysis Summary Report

  4. Scan the report for any smoking guns. Thread call stacks may be particularly useful. For example, this stack trace tells us that our service crashed while handling a button press. (This is not surprising though – that is what we did to force the crash in our testing!)


    Windows Service Call Stack

    Hopefully you will find a telltale sign to help you identify and fix your problem.

Also Find Memory Leaks in your Windows Service

If your windows service is consuming too much memory instead of crashing, configure the collector to watch for memory leaks:


Find Windows Service Memory Leaks

The final report will detail all outstanding memory allocations.

 

Good hunting!

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AlwaysUp 9: Improvements for running Dropbox/Google Drive/Box Sync/OneDrive 24×7 in the background

Stop Copies before Starting the Service

We are pleased to announce the availability of AlwaysUp version 9.0, our market leading run-anything-as-windows-service solution used by thousands worldwide!

New features include:

Better support for Dropbox, Google Drive and other Applications

Programs that allow you to run only a single copy at a time would occasionally prevent AlwaysUp from starting its own copy in the background. For example, if someone started a copy of Dropbox on their desktop, trying to launch a second copy under AlwaysUp would lead to Dropbox exiting quickly and the service failing to start.

Checking the new Stop all copies of the application running on this computer setting on the Startup will resolve the issue. Instead of simply trying to launch a second copy of your program, AlwaysUp will first stop any existing instances, ensuring that its own copy will start smoothly.

Stop Copies before Starting the Service

We recommend using this setting with the following applications:

… and any others that should only run a single instance.

Additional Power Management Options

To prevent your computer from automatically going to sleep while your important program is being run by AlwaysUp, check the corresponding box on the Extras tab:

Prevent the PC from Sleeping

Reduced Event Logging

As it runs your application as a Windows Service, AlwaysUp writes information, warnings and errors to the Windows Event Log. Usually this is a good thing, keeping you up-to-date on your application’s comings and goings, but it becomes rather “noisy” for applications designed to start and stop frequently. For example, if you have a batch file configured to run every ten minutes, more than 20 events will be generated per hour!

Check the new Minimize event logging as the application stops & restarts box on the Restart tab to improve the situation. Afterwards, you should only see a message when the application starts or terminates unexpectedly. Normal/expected stops and restarts will not be recorded.

Minimize Windows Service Event Logging

 

Be sure to check out the AlwaysUp Version History for the full list of features, fixes and improvements included in this release.

Enjoy!

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AlwaysUp not Starting your Application? Troubleshoot with the Command Prompt

If you find that your application is starting and then quickly stopping when you run it with AlwaysUp, your application may be trying to report an error message that you simply cannot see. In this situation, we recommend starting your application from a command prompt running as a service, to find out if something useful is being written to the console.

How to start CMD.EXE as a service on your desktop

  1. Highlight your troublesome application in AlwaysUp and select Add Copy… from the Application menu.

    (In this guide, our “StartServer” batch file is failing for some unknown reason so we’ll work with that entry…)

    Add Copy

  2. In the Add Application window that comes up:

    1. In the Application field, enter the full path to the windows command prompt. This is:

      C:\Windows\System32\cmd.exe

    2. If there is anything in the Arguments field brought over from the application you copied, please remove it.

    3. Change the Name field to something meaningful. We have entered “CMD Testing” in this guide.

    4. Set the Start the application field to Manually, from AlwaysUp. We don’t want this command prompt service to start automatically at boot.

    Command Prompt Service - General

  3. If you have specified a user on the Logon tab, switch over there and re-enter the password (a security measure).

    Command Prompt Service - Logon

  4. Those are all the changes we need to make so click the Save >> button to record your new service. It will show up on the AlwaysUp console soon.

    Command Prompt Service Saved

  5. Next, start the new CMD service on your desktop by selecting Application > Start “CMD Testing” in this session:

    Start Command Prompt in Session

    In a few seconds, the familiar black box will pop up on your desktop:

    Command Prompt Service Started


  6. And finally, in the command box, type in the full command line you gave to AlwaysUp — application & arguments. Be sure to specify the exact values that you had supplied to your AlwaysUp service! Please cut & paste to ensure accuracy.

    Hit Enter to run your application and pay special attention to what is written to the command prompt.

  7. Hopefully at this point your application will tell us what is wrong! In our case (pictured below), the batch file can’t find the JAR file it is expecting…

    Command Prompt Showing the Error Message

    Resolving the problem

    Common errors include:

    • Running the wrong executable (doh!)
    • Not properly quoting command-line parameters (smacks forehead)
    • Not running from the correct directory (which you can fix by adding the folder on the General tab)
    • Insufficient permissions to access a required resource (are you using the right user on the Logon tab?)

    The AlwaysUp Frequently Asked Questions (FAQ) will help you resolve these and other common issues. And if you’re still stuck, please feel free to contact us for fresh ideas and expert advice 🙂

    And don’t forget to cleanup when you’re done…

    Once you’ve fixed the problem and verified that your application can start normally with AlwaysUp, please feel free to remove the CMD service by highlighting the entry in AlwaysUp and selecting Application > Remove.

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