how can i stop 'save as' popping up all the time

[bluegravy]

when i am repeatedly saving the same file using 'save' about every six times i get prompted into 'save as'. this is a bit like the feature that makes you buy the product when you are using the trial version. I have a valid licence which i have paid for so i dont understand why it keeps doing this. i have had a good look around preferences etc and searched the forums. please help. thanks.