While editing a document in Word 2007 the document suddenly becomes read only

For work, I received a new computer with Word 2007.

As I'm working on a document, everything will be going normally (write a bit, save, write a bit, save, etc) but at some apparently random point, the document will suddently become read only. I can not isolate the trigger for this but I do know that it shouldn't be doing it.

Periodically, I've done searches on this problem and have found others with similar reports, so its not just me. One suggest was to turn off the auto-save but the problem persists.

I'm saving the document on my hard drive in my Documents folder (actually its in a sub folder but that shouldn't matter).

The only usual thing about my usage might be my over use of ctrl+s. At times I will ctrl+s after each word but again I see not particular pattern with my usage and the problem.

Answer

Is it possible that an over-ambitious anti-virus, that is set to scan Office documents, locks the document every time you save it ?

Try to disable the anti-virus for some time to see if this solves the problem.