Avast thinks file which Steam needs is malware

Avast keeps blocking file called vstdlib_s.dll in Steam folder. Steam needs it and when i try to start Steam it always says “Updating Steam” and then Avast warns always of that file and Steam wont start. What happened, none of my Steam files never before been detected. I would like to get Steam work fast.
Last message of Steam is after 99% that "ERROR: Can not open file vstdlib_s.dll and then it closes.

http://forum.avast.com/index.php?topic=101884.0

http://forum.avast.com/index.php?topic=102103.0

pondus, one of your links points to this topic

All i have found other topics are other files, not vstdlib_s.dll. :-\

well the point is that there is already started topics about steam issue… so if you keep all your steam post at one place :wink:

That’s it? Your answer is “let’s keep the place tidy?” You could have indicated that in your reply.

<sigh…> Does anyone have any helpful solutions to this problem?