You notice that you have following errors in SAP R/3, Database Alert.log file, or BR*Tools log:
ORA-00372: file cannot be modified at this time
Short dump: ABAP runtime error DBIF_RSQL_SQL_ERROR
SQL error 372 occurred in statement
ORA-00372: file xx cannot be modified at this time
ORA-01110: data file xx: <data file full path>
BR0324W Insertion of database log header failed
Firstly please check and follow note 328785 - ORA-00376: File cannot be read at this time.
If after you executed the calls in steps 2, 4, and 6 of note 328785, they do not return any lines. But you still have the problem. This is caused by tablespace is with status READ ONLY. In this mode, you can not modify the data files under this tablespace.
Please carry out following steps:
1. Start SQLPLUS:
sqlplus "/as sysdba"
2. Check whether tablespaces are set READ ONLY (now the database is in OPEN state):
SELECT TABLESPACE_NAME FROM DBA_TABLESPACES WHERE STATUS = 'READ ONLY';
3. If tablespaces are returned, reset them to ONLINE:
ALTER TABLESPACE <Tablespace_Name> READ WRITE;
4. If the call in step 2 does not return lines anymore, the problem is corrected.