QuickBooks Error 80029c4a is a common error that occurs in the Desktop version. It prevents you from opening your software, and from accessing any of your company files. Usually, this error is only present in the versions of QuickBooks Desktop that were released before the year 2016. In case you need professional help with this problem, please contact the QuickBooks Desktop Support Phone Number. It is a toll-free number that operates on a 24*7 basis.