I was having eM Client in my laptop, I took backup properly and saved the backup files in external hard drive. After that I formatted my laptop when I again reinstalled the eM Client, I tried to import the backup files but I’m facing problem to import them, when I checked and found backup files are in .dat files. Now I don’t know how to import these backup files as there is no option I can see.
The backups made from eM Client are saved in zip format in the folder \Documents\eM Client by default. Hopefully these are the files you saved to your external hard drive.
To restore, you don’t need to open the zip file or import the contents. Just make sure the zip files are in the \Documents\eM Client folder, then choose Menu > File > Restore from within eM Client. If you have multiple backups, you will be prompted which one to restore.