POSIC will run on Windows Vista and Windows 7, but there are a couple of things that you should bear in mind:

1. Installing POSIC
   After you have downloaded the installation program (and saved it somewhere you can find it, preferably on your desktop), right click on the file and select "Run as administrator" to install POSIC. POSIC will be installed by default in the folder C:\POSIC. If you are installing POSIC for the first time, please do not change the default folder.
   
   
2. POSIC Help
   Vista and 7 do not ship with the file WinHlp32.exe which is used to display old style help files. This might not be a problem for you as you can always open the manual, but if you want to be able to display "Help topics" from the Help menu you will need to download and install the file from the Microsoft Web site. You can download it here.