Outlook keeps its pop and imap mail account emails in a *.pst file which is microsoft specific.

You can use a converter to convert *.pst files into mbox files and then import those mbox files into a 'Local Folder' mail account folder. You might need to purchase the converter.

You could export the outlook emails as .eml files and import them into Thunderbird. This should be possible in Outlook. Right click on email and choose to save as eml file. Save to a folder you created on desktop for those .eml files.

This addon tool called 'ImportExportTools' will allow importing of *.eml files into a folder or allow importing of mbox files into eg: 'Local Folders' Mail account or into a folder. https://addons.mozilla.org/en-US/thunderbird/addon/importexporttools/

Download the above addon extension to desktop or downloads folder. In Thunderbird 'Menu icon' > 'Addons' click on gear icon and select 'Install addon from file' locate the *. xpi file you downloaded and click on Open You may need to restart Thunderbird at prompt.

Right click on eg: Inbox OR 'Local Folders' mail account or any folder in 'Local Folders'. Select 'ImportExporttools > then either choose 'Import mbox file' or 'Import Messages' for .eml files.

I do not synch google contacts but it is possible. Here is some good info on this. https://support.mozilla.org/en-US/kb/using-lightning-google-calendar

amandasey That link points to an advert. Are you supporting this blatant advert for SysInfoTools Software

the person who initially provided that spam link no longer has a profile, probably because they spam adverts.

Forum spam consists of posts on Internet forums that contains related or unrelated advertisements. This is against the rules of this support forum. https://support.mozilla.org/en-US/kb/forum-rules-and-guidelines