Do you agree with problem description Sridhar gave above ? If yes, As Sridhar mentioned that you need to right click the secondary & set "enable data access" .. & that is not happening automatically ..... in that case you still have a workaround right ? how is that blocking usage ?
Ok coming back to problem, do you see any error/message in logs once this switchover is done ? Did you ran a health check on VVR to see if VVR component is healthy...
In unix, we need to set a diskgroup authentication, I hope something like that would be available in windows, (though not sure), has this been setup ?
Gaurav