The image shows a faulting program ashWebSv.exe web shield and also a faulting module iFW_Xfilter.dll, avast may well be using a module that has a problem. This is still flagged as a problem with avast but the module iFW_Xfilter.dll does not belong to avast.

This is the true problem, the iFW_Xfilter.dll, do a search for this file and let is know its location, when you find it check the file properties and see who it belongs to ?
What is your firewall ?

I did a google search for iFW_Xfilter.dll and only got one hit, to me that is strange.

O10 - Unknown file in Winsock LSP: c:\arquivos de programas\iolo\common\firewall\ifw_xfilter.dll O10 - Unknown file in Winsock LSP:

Yahoo returns a further hit, http://www.spywaredata.com/spyware/malware/ifw_xfilter.dll.php this shows clean/safe, but I don’t like such a lack of hits in a search.