Backup file created by QuickTax, a program used to file Canadian tax returns; contains a copy of a corresponding .Q08 or .Q09 tax return file; auto-saved by default each time a tax return file is saved.

NOTE: If a Q08 or Q09 file becomes corrupted, users may rename the QBK file extension from ".qbk" to ".q08" or ".q09" and open it. By default, QBK files are saved in the following directory, where "xxx" is the year: Documents and Settings\User\My Documents\QuickTax\2xxx NOTE: In 2011, Intuit Canada changed the name of QuickTax to TurboTax.