NOw after going through this discussion, I am telling you what I think the prodedure might be for infection from those files...this is just a guess...I am not ver ysure but I think that this is the closes I can get to the rpocess...Here I go:

When a person double clicks the file with an extension which is unknown just like HQX in most cases, windows tries to first see if it is a rgistered file type. If it is not then it will start the service wihch asks the user to tell which program to be used for opening that file, during that very moment, the file is read to gain more information like g=signature of file and the meta info. In most cases, such files ( which often come in various extensions and are reported as X-application by norton) have some thing in their beginnign which tells the program which ask for the slection of software to open that file to execute an instruction from within the file. This is where they get executred and infect the computer.

I Think that is the only way Windows would get infected by those files.

Please tell me if I am right or wrong.

Thanks...