You should always make eM Client backups incase you need to restore for any reason. Suggest you do that in future either automatically via the “Menu / Settings / General / Backup” or regularly via “Menu / Backup”. if you backup manually you can see when thats completed in Show Operations via the dropdown on the right of Refresh.
So as you now have the latest V10 installed if you don’t want to upgrade to a new V10 license then see the following eM Client support article below on how to downgrade back to V9.
How can I downgrade back to eM Client 9, eM Client 8 or older?
Posted by Olivia Rust on 21 July 2020 16:43
Note: These same steps can be used to downgrade from a BETA version to the current eM Client official version - just uninstall the BETA and reinstall current version from the website
Our databases are not backward compatible for older versions and once you upgrade your database to accommodate the new version, you cannot just simply install an older version over it.
If you have a backup of your database from eM Client 9 or older you can skip any export. If not, you will need to export local data before the downgrade to keep them.
For accounts set up with IMAP, Exchange, Office 365 or iCloud this is not an issue, as setting these accounts as new will synchronise messages and folders back from the server.
For POP accounts and any data in Local folders, export them first via Menu > File > Export and once you downgrade, you can import them back via Menu > File > Import.
The steps to downgrade on Windows are to:
- Export any local data you need to keep (Menu > File > Export)
- Uninstall eM Client 10
- Either delete the database or rename it
- Install your preferred older version of eM Client (You can find older versions in our Release history)
- Restore from the backup (Menu > File > Restore) or create your accounts anew and import your local data back in (Menu > Accounts, Menu > File > Import)
If you want to just rename your database, the default location is in C:\Users%username%\AppData\Roaming\eM Client
The steps to downgrade on macOS are to:
- Export any local data you need to keep (File > Export)
- Uninstall eM Client 10
- Either delete the database or rename it
- Install your preferred older version of eM Client (You can find older versions in our Release history)
- Restore from the backup (File > Restore) or create your accounts anew and import your local data back in (eM Client > Add account, File > Import)
If you want to delete or rename your database, the default location is in /Users/User Name/Library/Application Support/eM Client
If you upgraded by accident and aren’t sure if you need to downgrade manually, please see the article on this topic - This version of eM Client is newer than what your current license permits.