I get this error message when I try to run it from the Start menu.
The applicaton has failed to start because it`s side-by-side configuration is incorrect. Please see the application event log or use the command-line sxstrace.exe tool for more details.
It appears that Avast is no longer running how do I fix this?
You didn’t say what kind of Windows OS you have however here is a link at vista64.com that explains what the problem is; i.e. corrupted Windows files, and how to fix it.