I'm running a domain made of up multiple servers, all which host websites that are configured to have anonymous access through IIS. They all use the IUSR built in accounts have an IIS control the password. Last week, all the sites started to prompt for a userid and password where they never did in the past. IIS appears to be configured properly, and I tried to restore the IIS metabase back to a date where it worked, but this had no effect. I was thinking about deleting the IUSR accounts and trying an active directory account instead. Anyone know what would have caused this or how to fix it?