IIS problem with Drupal - Update manager: Update failed! Directories are locked by php-cgi.exe
The reason for php-cgi for having the Lock is because of the "peculiar" way windows handles file access, and php/iis handles "caching". 
Basically you just created the directory and tried to access it, but the handle that created it was not released (so it was still locked). 
This is not a drupal issue, its an IIS/PHP issue
And there is no known workaround that I could find. 

Basicly, do the base advise of not using IIS is the best, I have seen this problem in more than just drupal with IIS that I solved by moving to apache HTTPD (on win32).
Mind you that was for back at school, with a project where I was required to use windows 2000. 

the best way I know of running drupal on windows is through apache (because of the internal handling of php).