DD716TED wrote:
I just updated my DW's computer to Microsoft Office Pro 2016. It works fine except that we cannot get Thunderbird to be our Default email client.
If this were me, I'd backup my Thunderbird (TB) profile files and uninstall TB completely including existing profiles. Make sure to restart WIN 10.
Re-install TB with the latest version, but "don't" setup any email accounts. Go back into WIN 10 default apps, and set TB as default email client. Click on any "mailto:" link and check if it brings up TB client? There won't be any accounts, so TB will ask you to set one up? You can then transfer your saved TB profile files and modify .ini file if necessary, which will restore your email accounts. Or set them up again following TB prompts. TB profile instructions on Mozilla's site.