Use the new application log

What causes this issue?

The new application log is already active in your system.
The following transactions have been replaced:
Old Transaction,,New Transaction
KE1F,,KE1FN
KE29,,KE29N

System Response

You can continue to use the old logs. However, the old logs serve only
for showing old log entries that are not available in the new log. For
the new logs, however, we recommend that you use the new log
transactions because not all actions can be performed in the old log
transactions or not all information is up-to-date. In particular:
The <LS>Reverse </>function for top-down distribution can only be run in
the new transaction.
The <ZH>status </>is not updated in the old log.

How to fix this error?

Use the new log.

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.