Thanks for replies. Noel I'm glad to say your suggestion to click the mixer icon on the toolbar to close the mixer has worked in that the mixer is no longer loading along with biab. I was clicking on the close X sign on the mixer dialog window as I thought it did the same job to close the mixer but it seems not, if I only click on the X then the mixer will close but load again after biab starts and the subsequent error messages first.

Peter thank you very much for having a look at this and your suggestion to return to factory settings, I have already tried that and reinstalled a number of times, but the error message when trying to open the mixer remains, I am very curious if this mixer problem is mainly confined to windows 7 32 bit. Maybe if you have that OS in the office somebody might give it a try, if not already done so. 2011 is running perfectly.

thanks very much
axey