Not implemented 501 - what is this?

[sem_scotty]

I get a 501 error for some pages when using a spider simulator - what does this mean, and what should i be fixing?

[pageoneresults]

The server does not support the functionality required to fulfill the request. This is the appropriate response when the server does not recognize the request method and is not capable of supporting it for any resource.

Could be any number of things. What type of pages are you running through the simulator?

Reference

• W3C - 10 Status Code Definitions [w3.org]
  

[sem_scotty]

they are 301 redirects to pages that used to be indexed.