It does this when you have had an external drive or Pen drive plugged in, and taken out then try to run WinAso. Reboot without any external drives or flash drives and try again, I think you will find it's OK. I have had discussions (Not very successful) about this with their support, they blame Vista, and say it will be eventually updated and sorted, but I have my doubts.
you're a star. Tried disabling my AntiVirus, but still failed, so used one of the suggestions in your link to change all the removable drive letter assignments and great - it worked. To be fair, it was also amongst the list that gengiscant googled for - thanks to you both. Really is resolved now.
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