When the device requests a certificate from NDES/SCEP/MSCEP, it sends a string of over 2700 characters as part of the request. This string is larger than the default size for query strings and will result in a 404.15 error. The default query string length must be increased to accommodate this large string.

  1. Open a command prompt from the Windows Desktop.
  2. Enter the following string:

    c:\windows\system32\inetsrv\appcmd.exe set config -section:system.webServer/security/requestFiltering /requestLimits.maxQueryString:"3072" /commit:apphost