Thumbnails As ? in ASP.NET

Hi,

My user-uploaded image thumbnails are appearing as question marks in the ckfinder browser.

- I've reviewed http://docs.cksource.com/CKFinder/Devel ... stallation
- I'm running version ckfinder v1.4.3 that I purchased with the one-site license.
- I'm running this in ASP.NET (v2.0.50727.4927).
- I've given the user <SERVER-NAME>\IUSR All (including write) permissions on my /ckfinder/userfiles/
- I've got a copy of CKFinder.dll in my sites bin and have added a reference to it.
- In IIS, I DO have Execute Permissions set for the /ckfinder/ folder
- My config.ascx CheckAuthorisation() returns true
- BaseURL = "/ckfinder/userfiles/"; | Thumbnails.Url = BaseUrl + "_thumbs/"; | Thumbnails.Dir = BaseUrl + "_thumbs/";

When using the site, I'm developing on my local. Even though I purchased the license for http://www.mysite.com. I've created an entry in my hosts file for 127.0.0.1 http://www.mysite.com and is resolving properly.

When testing on my local and I try to upload a file, a file is successfully uploaded to /ckfinder/userfiles/images, but not /ckfinder/userfiles/_thumbs/Images. However, if I manually (in windows explorer) copy a file from /ckfinder/userfiles/images --> /ckfinder/userfiles/_thumbs/Images/ then the thumbnails show up in the ckfinder browse window. (granted, they're large, not thumbnails. but you get the idea. )

Because files can be uploaded, and when manually entered in the _thumbs dir they appear, it seems to me that there must be a problem with the code that's supposed to create the thumbnails. I do not have PHP installed - but was assuming I didn't need it if this was meant for ASP.NET.

Thoughts or suggestions? Thanks in advance!