Downloaded latest version and find that it requires cash and makes backward versions probably inaccessible. On opening I get a message that “This version of eM Client is newer that what your current licence permits.” So I can’t open it to go back.
System restore then gets stuck on restoring the registry, using two different restore points, so I can’t get back that way either.
To revert to version 7 you may need to have a backup made from within eM Client before you upgraded. That is because the database structure is very different in version 8, so is not backwards compatible. If you do not have a backup from version 7, you will need to export any Local Folder data before you uninstall.
Messages, calendars and contacts synced with a server will not be lost so no need to export them.
First make a backup using Menu > Backup, just in case.
Then uninstall eM Client making sure to delete the database directory when asked. This will delete your database that was converted from 7 to 8, but you cannot use it with version 7 anyway.