27 09 2009
IIS won’t start – Error 13: The data is invalid.
After restarting my virtual development machine IIS was not able to start anymore. I checked out if there is something reported to Event Viewer and I found the following error message –Error 12: The data is invalid. It turned out that during shutdown of my virtual machine IIS config file was ruined. Solution to my problem was very simple.
IIS configuration is in file c:\windows\system32\inetsrv\applicationHost.config. In my case this file was same by size as before but it was filled with null bytes. When changes are made to this file then previous version is backed up to c:\inetpub\history\ directory.
I copied last working configuration file from history directory to inetsrv directory and started www service. Luckily, everything works again.
If you need more specific description about this error then GrinGod blog has very good posting to read: When IIS Wont Start – Error 13.