"All File Formats" disappeared from IMPORT drop-list suddenly

I share the same computer with a co-worker.  I used to be able to click the "import" button and the default setting allowed me to import anything, for the file extension drop-list was "ALL FILE FORMATS.  All at sudden, "all file formats" disappeared, and the file extensions shown on the drop-list does not include JPG files.  

I asked the co-worker if he changed any settings.  He answered, "no."  

Although I could use other program to open JPG files and save them as TIF or PNG, it's pain going through the process.  All the files I could get to be used are all JPG files.

How can I change it the setting back to have ALL FILE FORMATS as default?  Thanks