The XPCOM message indicates a corrupted installation. That can often be fixed by installing again over the existing version. Regarding the local folders, these steps may help:

1. locate the local folders files within windows file explorer on old PC and copy to external media
2. on new PC, install the addon 'importexporttools'
3. highlight the Local Folders entry in left sidebar, rightclick, select the importexport menu option to import mbox
4. now, locate and select one of the missing local folders files from the external media (ignore any files ending in .msf

if You are not sure how to locate the files on old PC, do this:

1. on desktop, enter %appdata% in the windows search box on task bar. that should open at appdata/roaming
2. now, click the thunderbird folder, then the profiles folder, and your profile will be there. Look in the Mail\Local Folders folder for the files you want. If you are unsure, please post a screenshot of what you see in the profile folder.

Wo sind denn die lokalen Ordner bei windows 8 auf dem alten PC ?

Welche Endung haben Sie bzw. Wo werden Sie automatisch gespeichert ? Ich habe damals keine manuellen Einstellungen vorgenommen, alles so wie Thunderbird es vorgegeben hat.

Ich hoffe so sehr sie zu finden. DANKE

I have not worked with windows 8, but try this: - at desktop, enter %appdata% in search box on task bar. that should bring up windows file manager at the appdata/roaming folder - now, click the thunderbird folder and then the profiles folder. your profile is in that folder. there may be more than one profile folder, so look in each to look at last update date. Local folders are in the Mail/Local Folders folder. Ignore the .msf entries. If unsure what you have, post a screenshot of what you see.

Danke schon mal recht herzlich, hört sich an, als wenn ich es schaffen sollte.. ich werde es morgen probieren