Welcome back. I have not used Hash in a long long time either but I still like to check their web site. I have a dongle too :) I started on the amiga...
I think if you have a 32 bit system and are trying to install the 64 bit version of AM, then it will not work. If this is not the case and have an very old version that works on XP, i would right click the setup icon and click on properties. Then check the compatibilty tab and tell the program to be compatible with XP service pack 3. That should let you run the setup.
Best
PO