Virus Scan or Clean-boot
Check the computer's health status by running a virus scan. Viruses can infect systems or legitimate files of Windows. If a virus has infected dwwin.exe, you need to allow anti-malware or an online virus scanner to disinfect this file. You should not simply replace dwwin.exe because there are maybe other viruses or malware that may be residing in the computer. Replacing system files is only recommended if the file is not infected or the computer is malware-free.
You can also use standalone anti-malware programs to scan the computer: Malwarebytes' Anti-Malware, Hitman Pro, or Emsisoft Anti-Malware.
If the computer is not infected but you continue to experience a dwwin.exe crashes with AVG Free or paid editions problems, start troubleshooting to determine which driver or software conflicts with AVG, and that triggers the dwwin.exe crash report message. To troubleshoot, perform a clean boot in XP or perform a clean boot in Vista or Windows 7.
You can also use Event Viewer in Windows to determine which processes or any installed application is really causing the crash of Watson Client and AVG.
If no other application is causing dwwin.exe to crash other than AVG, you might want to report this issue to AVG support forums.
Reference: Microsoft Support - http://support.microsoft.com/kb/930857
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