Upgrade V8 to V9 crashed - File "fil...." cannot be found in MailClient.cab

The installation of the latest version 9 was aborted with the following error.
Same message if I try to install in repair mode.

After that, the installation could only be aborted.
Conclusion: no functioning emClient available on the computer.
What can be the reason?
If I can’t repair How can I reactivate the previous version without losing all historical data?