This error can result if you are attempting to launch ACT! by double-clicking the Act##.exe (where ## equals version number) file, or you have used one of the files when creating a shortcut. You must use the ActSage.exe file to launch ACT! by Sage 2007 (9.0) or later version. Ensure the name of the file is ActSage.exe and does not contain any other characters or spaces.
If you are receiving this error when trying to access an ACT! Premium for Web database via the Internet, it may be necessary to reset Internet Information Services(IIS) on the web server to enable access to the web database. For information on resetting IIS, please see the following Knowledgebase article:
Answer ID: How to Reset IIS (Internet Information Services)