Transfer Fossamail folders

[BrianCarver]

I have used Fossamail for some time now and have found it O.K. I have just upgraded from a 32 bit win 10 P.C to a new 64 bit win 10 P.C.Before doing so I followed instructions from your web site and copied the Fossamail folder from the old machine and kept it safe. I then downloaded and installed version 38.1 on to the new machine. I then followed the instructions and copied the saved Fossamail folder to the correct location, before opening Fossamail.
After opening Fossamail I found the account was set up O.K. and I can send and receive mail. However I now find that all my Local folders etc, some of which I transferred from Outlook 2003 or Thunderbird but most of which I had created myself now longer show.These folders contain all my email history (personal social and business ) and I cannot afford to lose them They are correctly located in C:Users\xxx\appdata\roaming\Fossamail, and includes profiles etc with a size of 472MB, has 22 folders, the largest being Mail (444MB).
My question is, is there a way that I can make Fossamail show all these these folders so I can use them.
Any help will be appreciated