Well I didn't say to disable the mail shield only the inbound scanning, I don't know if in disabling the mail shield completely the plug-in would still be expecting to have it running presumably, hence the no emails.
It is strange that this only happens in MS Outlook and not in Thunderbird (the malformed emails), unfortunately not being an MS Outlook user I can't be any practical help on that.
The only thing I can thing to do now since a repair didn't do anything is to do a clean reinstall:
Download the latest version of avast (if you didn't save it previously) and save it to your HDD, somewhere you can find it again. Use that when you reinstall.
Download the avast! Uninstall Utility,
find it here ensure you get the version5 one (it has uninstall tools for both 4.8 and 5.0), aswClear5.exe and save it to your HDD.
- 1. Now uninstall (using add remove programs), reboot.
- 2. run the avast! Uninstall Utility from safe mode, first for 4.8 if previously installed and then for 5.0, once complete reboot into normal mode.
- 3. install the latest version, reboot.