mssprxy.dll is corrupted and can't be fixed - what can be done?

Hello,

I'm getting the following message whenever a tab is closed in Google Chrome. I'm posting the question here, since Chrome is just a symptom to a bigger problem (already re-installed it twice).

The message: mssprxy.dll is either not designed to run on Windows or it contains an error. Try installing the program using the original installation media or contact your system administrator or the software vendor for support.

I guess the 'vendor' is Microsoft...

This is Windows 7 Home Premium that came with the Toshiba L500 laptop. No installation media available, of course.

These are relevant lines from the CBS.log, the result of 'C:\windows\system32\SFC /scannow'.

2011-07-28 08:45:44, Info                  CSI    000002fc Hashes for file member ??\C:\Windows\SysWOW64\mssprxy.dll do not match actual file [l:22{11}]"mssprxy.dll" :

  Found: {l:32 b:6vL5jP1E3+y/nSzhN7E6hsA7ytwkG9QQPopTpAWNaG4=} Expected: {l:32 b:4e3OYhayQDeyQ6xozuvVEGRrLv1wvBGOaDA/nthdGXM=}

2011-07-28 08:45:44, Info                  CSI    000002fd Hashes for file member \SystemRoot\WinSxS\wow64_windowssearchengine_31bf3856ad364e35_7.0.7601.17610_none_dbd0d3376679543d\mssprxy.dll do not match actual file [l:22{11}]"mssprxy.dll" :

  Found: {l:32 b:6vL5jP1E3+y/nSzhN7E6hsA7ytwkG9QQPopTpAWNaG4=} Expected: {l:32 b:4e3OYhayQDeyQ6xozuvVEGRrLv1wvBGOaDA/nthdGXM=}

2011-07-28 08:45:44, Info                  CSI    000002fe [SR] Could not reproject corrupted file [ml:48{24},l:46{23}]"??\C:\Windows\SysWOW64"[l:22{11}]"mssprxy.dll"; source file in store is also corrupted

What can be done in order to remedy this situation?

Thanks!

Dotan