QuickBooksForum.com.au

Hi, we have the below Event appearing very often, could you please suggest us the best feasible solution to overcome the same.

Event: 4
Description: An unexpected error has occured in "QuickBooks":Returning NULL QBWinInstance
Handle

Look in your QBWin.log file (in your appdata)...

If you are getting the error:
QBWINDLL.c (307) : MESSAGE: Mon Mar 08 15:42:19 LVL_ERROR--Returning NULL QBWinInstance Handle
In the QBWin.log file as one or more of the first lines.

The reason is:
When QuickBooks starts up, it goes out and looks for "add ins" to load. If when doing so, it finds none, the find routine returns a null.

So if you see this error message at the beginning of the log file, it really means that you have not subscribed to any of the add-ins.
 
Once QuickBooks determines that there are none, it appears that it caches this info and subsequent restarts of QuickBooks during a computer session will load much faster.

However, if you reboot your computer, it will again go out and look for these add-ins.

If you look at the log every time QB starts, you will see the errors.

If this error is posting elsewhere in the log file, it is probably being caused by something else.

BTW: This error, at the beginning of the log file, has nothing to do with your company file. It all happens before any company file is loaded... 

So, bottom-line - check your added 3rd party applications.