Illustrator not saving files as an AI

[#1]

Hi, 

Illustrator is not saving my files when resaving after editing as an AI but it will save it as a PDF. 

It makes it appear it is saving but doesnt actually save, 

Please help 

[#2]

In the preferences can you please try and turn off Background save?

Also: if this happens on a serve, plese try and save on the local disk.