Unspecified application error

What causes this issue?

Application "&V1&" detected an error when checking the entry "&V2&3",
but did not transfer a valid message.

System Response

It is not possible to say whether it will be possible to use this entry.

How to fix this error?

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

Procedure for System Administrators

Error message extract from SAP system. Copyright SAP SE.