noSuchObject

If a variable does not have an OBJECT IDENTIFIER prefix that exactly matches the prefix of any variable accessible by this request, its value field is set to noSuchObject.

noSuch
Instance

If the variable's name does not exactly match the name of a variable, its value field is set to noSuchInstance.

genErr

If the processing of a variable fails for any other reason, the responding entity returns genErr and a value in the error-index field that is the index of the problem object in the variable-bindings field.

tooBig

If the size of the message that encapsulates the generated response PDU exceeds a local limitation or the maximum message size of the request’s source party, then the response PDU is discarded and a new response PDU is constructed. The new response PDU has an error-status of tooBig, an error-index of zero, and an empty variable-bindings field.