SAVE button grayed out / unavailable

[safdc]

I am working on a project that has about 20 pages. Occasionally when I try to save it, the SAVE button is gray and not available to save the project. Even when I use SAVE AS the new saved file usually has the same problem with the SAVE button remaining unavailable. I have found however that if I simply add a new OBJECT such as a button temporarily, and then delete it, that the SAVE button once again becomes available, and I can then go ahead and save the project.

When this behaviour first occurred it was alarming since I have spent many, many hours on this project. Fortunately I discovered a workaround but it still seems that the problem should not be happening in the first place.

Is this a BUG in the software or is it something that I may be doing that is causing the SAVE button to be unavailable at times when I use the program?