Set database=4 trace on the DB Unload utility. Search for ORA-00001. Above that line you will find the SQL that caused the DB Unload to fail. For example:
update OH set OH_Name = ? where OH_Idnr = ?
Since we enabled the trace we can see the value for OH_Name and OH_Idnr. For example:
U00009909 TRACE: (BINDPAR: OH_Name ) 00007FFA9AA14B4F 000014
00000000 31303030 3030316B 5C5F554E 4958 >1000001k\_UNIX<
U00009909 TRACE: (BINDPAR: OH_Idnr ) 00007FFA9AA14C18 000004
00000000 48341200 >H4..<
The update would look like this (based on the information above):
update OH set OH_Name = '1000001k\_UNIX' where OH_Idnr = 1193032
The folder name '_UNIX' is preventing the DB Unload from finishing. To resolve this open the User Interface and locate the '_UNIX' folder and rename (do not delete). It is possible that multiple folders will have this problem. In that case repeat the steps above until the DB Unload runs without error.