Request-URI Too Long

What causes this issue?

The server is refusing to service the request because the Request-URI is
longer than the server is willing to interpret. This rare condition is
only likely to occur when a client has improperly converted a POST
request to a GET request with long query information, when the client
has descended into a URI "black hole" of redirection (e.g., a redirected
URI prefix that points to a suffix of itself), or when the server is
under attack by a client attempting to exploit security holes present in
some servers using fixed-length buffers for reading or manipulating the
Request-URI.

System Response

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

How to fix this error?

Procedure for System Administrators

Error message extract from SAP system. Copyright SAP SE.