You have configured IIS7 and you are facing problem opening a file which has '+' in its filename
You are facing this issue because the request filtering section does not allow the double escaping sequence.
To resolve this issue, follow below instructions:
- in the IIS webserver section, double click the 'Request Filtering' icon
- in the 'File Name Extension' right click->Edit Feature Settings...' the file 'web.config'
- check the option 'Allow double escaping' (this option is unchecked by defualt)
- repeat all above 3 steps for the 'defualt website' (or whatever you have given the name to your site)
- re-start the IIS
- you should now be able to open up the file name having '+' in its name.