Failed validation to synchronize with NextCloud Cardbook for Thunderbird › Forums › Main Forum › Failed validation to synchronize with NextCloud This topic contains 2 replies, has 2 voices, and was last updated by smokinjo 5 months, 4 weeks ago. Author Posts 24th December 2018 at 16:59 #2412 smokinjoParticipant I reinstalled my computer with LinuxMINT. All is going swimmingly, but a couple of glitches have come up. I enter the required URL(I copy this form the settings section of NextCloud), name and password as I have done before. But, it fails to validate. What else might I look for to get it to work. Thanks This topic was modified 5 months, 4 weeks ago by smokinjo. 24th December 2018 at 17:14 #2414 CardBookKeymaster with Thunderbird 60, try this (same issue with Lightning) : network.cookie.same-site.enabled = true —> false… 24th December 2018 at 19:59 #2415 smokinjoParticipant thanks!! Author Posts You must be logged in to reply to this topic.