Cannot generate query: Not possible to read variants

What causes this issue?

An attempt was made to read the query variant. The query variant
contains the selection conditions and additional settings that were
made when the query was created. For the variant to be read, the query
must first be generated. The generation terminates, however, with an
error.

System Response

The variant cannot be read. As a consequence neither the selection
conditions nor the additional settings can be determined. The query is
thus loaded without the variant information.

How to fix this error?

Procedure for System Administrators

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

Error message extract from SAP system. Copyright SAP SE.