So, I found a solution from here after searching on Google. The documents I served were in read-only mode. The problem is solved only after disabling it.

Thanks for replying. I am using Microsoft Office 2007.

Hello Friends. This is my first post in this forum. Recently I am suffering from an issue with my computer. Yesterday I saved some word documents from the office on my home computer by pen drive and I can't edit or modify them in any way. I don't understand why this is happening, and how this problem can be solved. Can anyone help me with this?