When uploading a profile image users should see a message similar to:
For clarification, if you instead use one of the listed file extensions (JPG, PNG, GIF or BMP) does the file upload successfully?
If not I would recommend creating a case in your customer group here in the Jive Community where the next available member of our support team can perform further investigations into your specific instance. Additionally, when you create the case if you could attach a couple of the files causing the behavior for them to use in their testing.
The problem occurs with a JPEG file with its natural extension .jpg. The file is below 1 MB. I will open a case.