Re-installing eM Client

I used to run Windows 10 and eM Client had half a dozen local folders containing archived emails. I had to give up on Win 10 because I found it unusable. I de-activated eM Client, put Wondows 8.1 on the PC then re-installed eM Client.
I use a data directory on my “D” drive so the old data is intact but eM Client doesn’t recognise these local folders.
How can I get eM Client to recognise them please? I have set up the data folder on the “D” drive as its data store.

This is the second attempt, the first seems lost.

I have had to re-install Windows 8.1 but in the process I have lost several hundred archive posts in my local folders.

I am using the same data folder, how can I recover these please?