Canoscan Twain errors and Skype failing to initialize

[Pentasaurus]

A SOLUTION.
Create a new Windows User account and run the troublesome apps from there.
In my case a Conoscan app on my Win 7 desktop suddenly started giving TWAIN errors. I tried everything including some very useful ideas from:-
http://weblogs.asp.net/jeffwids/archive/2009/11/02/canon-scanner-unable-to-open-twain-source.aspx
and
http://answers.microsoft.com/en-us/windows/forum/windows_7-hardware/twain-errors-when-using-canoscan3200f-on-win7/8f4c399b-52ab-4d37-8255-35d5b5cd0b3a?msgId=f4f1873e-9f23-449f-a86f-699512bb05fe
and
http://www.computerhope.com/forum/index.php?topic=132878.0

Nothing worked for me. I had to give up. (the scanner still worked on my other Vista laptop)

Later Skype suddenly failed to initialize on the same Win 7 desktop and gave disk I/O error. First line FAQ support support got me nowhere, From Skype support I got comprehensive instructions as to how to delete the app and clean the relevant registry entries. Before I did that I remembered I have another user account on the computer and Skype continued to work fine in it. So  I created a third account and the same installation of Skype initialized and worked. Then I tried launching canoscan which was still installed to the computer and it launched perfectly as well! Then I deleted the old user account.

So my assumption is that my regular Win7 user account had become corrupted. Creating a new account solved my problem for two apps. It's one more thing to try and simple for a computer administrator to do. I pass this on hoping to save others from tearing their hair out