Yesterday I had a problem where I needed to save an Excel file to wk4 format. We use Lotus Notes at work and sometimes when you need to import something is is best to save it in this format. When I tried to complete the save I received an error message that said “You are attempting to save a file that is blocked by your registry policy setting.”
Thankfully, one of my colleagues discovered Microsoft knowledge base article KB938810 that describes the changes that Microsoft made with Office 2003 Service Pack 3 and provides a process to let me save the documents as needed. There are some file types that are blocked from opening and some from saving.
By default, these file types are blocked because the parsing code that Office 2003 uses to open and save the file types is less secure. Therefore, opening and saving these file types may pose a risk to you.
So fixing the problem could pose a security risk. It is up to you to figure out how high of a risk that is for you or your company. For me, I only modified how Excel behaves and left the other security in place. To be really safe you could run the registry patch to let you save a file type then run the undo patch to set your security right back where it was. Be sure the read all of KP 938810 to understand what you changes you are making.