Thanks for replying so quick. Yes I am referring to the cleaner section.
Following your instructions it appears that when the empty recycle bin is ticked, this message appears. I suppose its not that important for me as I always empty this anyway.
However if you would like to help here is what the log file says:
23:38:52:692787[iNFO ] CCleaner v3.11.1541
23:38:52:692787[iNFO ] MS Windows Vista Home Premium 32-bit SP2
23:38:52:692787[iNFO ] Intel Core2 Duo CPU E6750 @ 2.66GHz
23:38:52:692787[iNFO ] 2.0GB RAM
23:38:52:692787[iNFO ] NVIDIA GeForce 8600 GT
23:38:52:692787[iNFO ] Application Started
23:38:59:291587[DEBUG] OnBegin | Preview = 0
23:38:59:291587[DEBUG] OnRuleStarted | 3003 | 3141 | Empty Recycle Bin
23:38:59:353987[FATAL] Critical Error
23:38:59:353987[FATAL] A critical error has occured in CCleaner, the application must now close.
23:38:59:353987[FATAL] The thread used up its stack