msgsrv32.exe

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Another possibility:

According to Microsoft article Q169987 titled, "Msgsrv32 Not Responding When Computer Hangs While Idle"

This behavior can occur when power management is enabled, and you have issues with programs not responding correctly to power management commands, for example, screen saver programs.

To work around this behavior, use the following steps:

Quit any running programs, and then test to determine if a specific program is causing this behavior. If you quit all running programs and the issue is resolved, one of the programs that was running is the cause of this behavior. If this does not resolve the issue, continue to step 2.

NOTE: This issue is often caused by screen saver programs.

To resolve:
Disable power management. To do so, click Start, point to Settings, click Control Panel, and then double-click Power.

In the Power Management box, click Off (or click the "Allow windows to manage power on this computer" check box to clear it).

Click OK.

Restart your computer.

If the behavior continues to occur, follow these additional steps:
In Control Panel, double-click System.

On the Device Manager tab, double-click the System Devices branch to expand it.

Double-click Advanced Power Management Support.

On the Settings tab, click the Enable Power Management Support check box to clear it, and then click OK.

Click OK.

Restart your computer when you are prompted to do so.

Source:

http://support.microsoft.com/directory/article.asp?ID=KB;EN-US;q169987

(Don't forget to REMOVE those pesky SPACES from the pasted URL.)

Maxwell

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Yet another possibility:

Users of Norton AntiVirus 4.0 and later versions have reported a slew of problems with the product, including annoying computer freeze-ups. With these system hangs, pressing Ctrl-Alt-Delete produces the error message "Msgsrv32.exe (Not responding)." ScanDisk may then create numerous temporary subdirectories (named DIR00000, DIR00001, and so on) that you can't easily remove.

Another AntiVirus-related problem may afflict your PC if you use Netscape Messenger as your e-mail program. The Messenger Inbox may take a long time to open, or it may not open at all. Messenger may stop responding when you try to open a message, and again your system may create many temporary files. Symantec confirms that the virus definitions dated June 16, 2000, and June 19, 2000, are responsible for these problems.

You should get rid of the mischievous virus definitions immediately. To update your virus definitions, choose LiveUpdate from within your version of AntiVirus or point your browser to Symantec's Virus Definitions page. To eradicate the temporary subdirectories created by ScanDisk, however, you'll need to run a specially designed utility from Symantec.

Source (and further information AND links):

http://www.pcworld.com/howto/article/0,aid,17680,00.asp

And, if you run AutoCAD Rel 14:

This behavior can occur if you have the Autodesk AutoCad Release 14 program installed on your computer, and the Graphics Display Interface (GDI) handle table has become damaged.

See this link for the resplution:

http://support.microsoft.com/directory/article.asp?ID=KB;EN-US;Q182567

Another possibly helpful link:

http://the-it-mercenary.com/forums/Help/posts/870.html

Good luck,

Maxwell

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A final comment:

Msgsrv32.exe is the Windows 32-bit Message Server. This essential program normally never appears in the Task List unless it has "hung"; it otherwise runs invisibly in the background performing a variety of essential services, a significant majority of which being to do with on-screen messages and notifications.

Recommendation :
As mentioned above this program only ever appears in the Task List if it has "hung". When that happens you will see "Not responding" next to it. Simply highlight it, and do an End Task on it (you may need to wait 5-10 seconds after the first "End Task" and re-do it). If MSGSRV32 hangs often, you will need to investigate.

Source:

http://www.answersthatwork.com/Tasklist_pages/tasklist_m.htm

Regards,

Maxwell