WORKAROUND
Check the following log file on one of the DCs to determine why this failed:
\ProgramData\Quest\Recovery Manager for active Directory\Logs\FRRestoreService64.log.
Search the file for "RESET_ADMIN_PWD".
There should be an error message pointing to why this has failed.
If it was the complexity requirements, the error will look like this:
STATUS
To address the failure, and make it more apparent as to why it failed, the following enhancement has been created.
This will add failure messages in the Forest Recovery console when a failure occurs.
Enhancement request number ADO-234511 has been submitted to Development for consideration in a future release of Recovery Manager for Active Directory.