IIS 7.5 clickonce application Config error

one of my team member reported me that he is unable to USE 7.5 as clickone deployment server, upon downloading click one application system was throw an exception in the log files that it is unable to download the ****.exe.config file. when i browsed the file IIS showed me 404.7 :The request filtering module is configured to deny the file extension.
which simply means that file is in restricted extensions.
so to resolved this issue i went to IIS manager then website then request filtering and then i added .config ext as allowed type. in file names extension tab.
remember to use this only when there is nothing special in the config files.
this can also be done by web.config using following article.
http://www.petefreitag.com/item/741.cfm

some more details here

http://technet.microsoft.com/en-us/library/cc754791(WS.10).aspx