Like the infamous Windows’s BSOD, Err99 is Canon’s DSLR dreaded error code for general operation failure. Whenever that’s a contact issue between lenses and body, bad battery, defective storage card or any ill exception to camera operation, the body will lock up and throw a catch-all error code of 99. No blue screen of death but the user has to remove and reinsert battery to get the camera up and running again once the error occurred. If you google err99, there are endless results of problems and suggested solutions to the must-distressed issue.
The newly released Canon EOS 50 can’t escape the faith of Err99, lengthy reports of such issues have been posted over numerous photo-related forums at its initial release. But the good news is the manufacturer has taken action- new firmware 1.0.3 has been issued to resolve Err99 and among two other bugs.