What does this error in the QBwin.log file mean and what do I do about it?
“LVL_ERROR--Returning NULL QBWinInstance Handle”.
This message indicates that Verify Data was unable to complete.
1. Rebuild Data twice in a row
2. Verify data again (it will probably show that there is data damage)
3. Now the QBWin.log will show new errors that will be useful in troubleshooting the data damage
4. If this does not resolve your issue, please review the data damage troubleshooting KB.