I’m only getting this message when I access the Production database. The statements still run but I have to click true the error message.
I’m having the same problem with Toad for Oracle 12.1.0.22 on Win 7.
Apparently this problem is related to setting a default schema in the Oracle option setting. In the past setting this option would allow the schema browser to default to the setting (and you avoided picking the schema from a long list of users/schemas). Now setting also means the editor displays the ORA-01435 error message with each SQL you run. Clear the default schema settings and the problem goes away.