I have encountered this problem with earlier wincache versions but have not reported any bugs yet. This problem occurs on multiple servers which use an identical configuration.
Current setup:
IIS6
PHP5.4.5
php_wincache.dll version 1.3.4.0.
When I enable the extension it works perfectly, however every now and then *something* happens resulting in a problem where every request to .php files fails. The only way to resolve this issue is to completely restart IIS. Recycling the Application Pool does not resolve the problem
The same time errors are displayed in: C:\WINDOWS\system32\LogFiles\HTTPERR (it also happens with requests to port 80)
2012-08-01 14:30:42 clientIP 52367 serverip 443 HTTP/1.1 GET / - 5326 Connection_Abandoned_By_AppPool DefaultAppPool
2012-08-01 14:30:42 clientIP 52368 serverip 443 HTTP/1.1 GET / - 5326 Connection_Abandoned_By_AppPool DefaultAppPool
2012-08-01 14:30:42 clientIP 53168 serverip 443 HTTP/1.1 GET / - 5326 Connection_Abandoned_By_AppPool DefaultAppPool
2012-08-01 14:30:42 clientIP 53177 serverip 443 HTTP/1.1 GET / - 5326 Connection_Abandoned_By_AppPool DefaultAppPool
I couldnt really find any known issues or fixes for this. If somebody could support me to resolve this problem please reply.