When the transaction log (.tlg) file and the company file (.qbw) are not compatible, QuickBooks Error Code 6190 appears, preventing access to the company file. It usually stops people from opening the file and shows up in single-user mode. This can be fixed by renaming the.tlg file or synchronizing the files. Need assistance with QuickBooks? In order to chat with an expert, dial 1.855.738.2784.