I do have avast! in Windows 98 without any of your described troubles...
That's because you don't have any folder called
Program (or even a file called
program.exe) in the root of your system drive.
For example, if you try to start a program called
C:\Program Files\Common Files\Microsoft Shared\Msinfo\Msinfo32.exeand you don't enclose the name in quotes, then Windows do the following (usually, at least):
1. Check for the file
C:\ProgramIf such a file exists (C:\Program.exe, C:\Program.bat, etc), the file is started and the rest is passed to it as command-line arguments.
2. If not, check for the file
C:\Program Files\CommonAgain, if such a file exists, it's started.
3. If not, check for the file
C:\Program Files\Common Files\Microsoft... etc.
If it's just a folder, the default "open" actions is performed on start - it's opened in Explorer.
Therefore, having a folder called
Program on the system drive (and installing your applications into
Program Files folder at that) is calling for troubles.
Anyway, I hope it will be fixed in avast.