I have told you the offending program's name/path;what more would you need?
I don't think you provided such info. Mentioning the name of a program that includes several MB (more than 100, by large) and a path used by all MSI installers, is not going to give any actual useful info.
Edit: Now I receive the same for a newly downloaded Firefox 9.0 installation executable;at this point i just think your program is possibly flawed in some manner.
Avast is not "our" program. We are simple users trying to help. And as already mentioned, if the only message you receive is that it is some decompression bomb, then you should READ the answers: it is NOT a malware, but just a general info.
If you actually received some other message of a real malware (not just general info), then please make it clearer so to provide you helpful info for you.