From Bill:
There's some information about what to do about this error in the help file
for the program, which you can open by navigating to it even if the program
won't open directly.
Here's what it says--the best search term to use is "release notes."
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* If you see a dialog box with the following message after you start your
computer or when you start Microsoft Windows AntiSpyware, you need to repair
or reinstall Windows AntiSpyware. The following message can also refer to
Error 102 or Error 103:
Warning: Microsoft Windows AntiSpyware has encountered a critical error
(Error 101). Please restart Windows AntiSpyware and run the program again.
If you continue to experience this problem, please uninstall the program and
install the most recent version of Windows AntiSpyware. You can use Add or
Remove Programs in Control Panel to uninstall this version of Windows
AntiSpyware.
You can repair Windows AntiSpyware using Add or Remove Programs in Control
Panel. Click Microsoft AntiSpyware and click Change. Click Next, and then
click Update.
If you see the critical error message again, uninstall Windows AntiSpyware
and reinstall it. To do this, use Add or Remove Programs in the Windows
Control Panel. Click Microsoft AntiSpyware and click Remove. You can
reinstall Microsoft Windows AntiSpyware at
www.microsoft.com/athome/security/spyware/software.
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Now--before you do all that, the developers at Microsoft are currently
interested in hearing from any user with an error 1xx.
Specifically they'd like to see the errors.log file from such systems. This
file is located in the folder in which Microsoft Antispyware was installed,
by default this is typically:
c:\program files\microsoft antspyware.
Please send this file to: (e-mail address removed)
with explanatory notes such as you've posted here.