You can use Windows Explorer and check whether the old profile still exists in the file system. For profile location see http://kb.mozillazine.org/Profile_folder_-_Thunderbird#Windows_Vista.2C_7.2C_8.1_and_10

I found the Archives on my windows PC, they are in a file marked Archives.sbd , they open in a thunderbird write page with the archive as an attachment in the top right corner of the page, the attachment opens in my firefox browser, unintelligable with pages of code with the emails somewhere on the page, is there any way of correcting this.

You'll have to import the mbox files (the ones without a file name extension). Make sure to manually create the desired folder structure prior to importing. For importing, install this add-on. https://addons.thunderbird.net/en-US/thunderbird/addon/importexporttools-ng/