Windows 10 will reach EOS (end of support) on October 14, 2025. For more information, see this article.

Avatar for Username

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

Echekwara usoro a. Biko jụọ ajụjụ ọhụrụ ma ọ bụrụ na ị chọrọ enyemaka.

I can't add a second device (Firefox Desktop, Mac) to the Sync service.

  • 1 nzaghachinzaghachi
  • 1 nwere nsogbu anwere nsogbu a
  • 4 views
  • Nzaghachi ikpeazụ nke philipp

pak0
pak0
more options

The error is "Unknown account: Sign up". I can log in just fine with the same account on https://account.services.mozilla.com/ though.

Particular to my setup: 

* My email address contains a "+". 
* I didn't remember my password, so I changed it to a new one in the Preferences on my first device (but, as I said, the new one works fine on https://account.services.mozilla.com/)
The error is "Unknown account: Sign up". I can log in just fine with the same account on https://account.services.mozilla.com/ though. Particular to my setup: * My email address contains a "+". * I didn't remember my password, so I changed it to a new one in the Preferences on my first device (but, as I said, the new one works fine on https://account.services.mozilla.com/)

All Replies (1)

philipp
philipp
  • Moderator
more options

hello, firefox 29 and upwards is using a different sync system which isn't compatible with accounts set-up in older versions. you'd have to create a new account to migrate to the new system (you can use the same mail there): Sync your Firefox bookmarks, history, passwords and more