Application Express :: Cannot Read Table In Other Schema Even With Qualifier

I had a situation last year where I could not login as myself or see any objects in my schema. Some code using APEX methods to create a new APEX user, and it finally worked.

The new user, ADMINUSERS suddenly had its password expire and I could not reset it, so I repeated last years’ effort but this time nothing worked.

Now I have a problem where I cannot even read a table if it is in another schema, even if I use the schema name as a qualifier. This happens even in SQL plus, except when I login as System I can read tables in other schemas if I prefix the table name with the schema and a dot. But this does not work with other users, even though I have granted the other users the role of dba.