legend?f=json : HTTP 500

[__Rich_]

(ArcGIS Server Enterprise Standard for .NET v10 SP5)

Hi,

Whenever I try to retrieve a legend for one of my map services with f=json (i.e. format = JSON) it crashes and returns:

{
  "error" : 
  {
    "code" : 500, 
    "message" : "An unexpected error occurred processing the request.", 
    "details" : []
  }
}

Are there any known scenarios that can cause this?

All the other services are fine and I can't see anything odd in the map document in Desktop, also nothing reported in the logs.

Also, calling legend with no arguments (returns the HTML page) works fine.

Any thoughts would be much appreciated 🙂

[__Rich_]

Update: Only occurs if the service is published using the MSD, if published with the MXD then it's fine.

Any thoughts as to why?

(no errors reported when running the analysis tool in ArcMap)