I have a website setup in IIS7 which is configured so that connections are as a user: IUSR_MyUser.
I also have FTP configured for this site, with a different user configured via FTP Authorization: FTP_MyUser.
The FTP user account has read/write configured for the entire site directory, where as the regular web user is more restricted.
I can login with FTP just fine, however when I try and update a file for instance, I get an "Access Denied" error.
Fired up Process Monitor to have a look at the error being generated, the important bits:
Operation: CreateFile Result: ACCESS DENIED Path: C:\PathToMyFile Impersonating: Computer\IUSR_MyUser
So it's impersonating the IUSR_MyUser account, which does not have permission to write.
How should I configure IIS / User accounts to attain the appropriate level of security for what I'm after here?