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Why has Thunderbird started prompting for Caldav at startup?

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  • Last reply by Lin

For the past few days when I open Thunderbird I get a message "https://caldav.one.com is requesting your username and password." (see attachment). I've never signed up for Caldav so I don't have a username or password. If I hit "Cancel" it proceeds as normal. If I enter my email address and log-in password it also proceeds as normal. In either case I have to go through the same process every time I open Thunderbird.

For the past few days when I open Thunderbird I get a message "https://caldav.one.com is requesting your username and password." (see attachment). I've never signed up for Caldav so I don't have a username or password. If I hit "Cancel" it proceeds as normal. If I enter my email address and log-in password it also proceeds as normal. In either case I have to go through the same process every time I open Thunderbird.
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All Replies (1)

"Caldav" is a protocol for synchronizing calendars, and one.com is a web site host, so "caldav.one.com" suggests that Thunderbird is trying to connect to a calendar on one.com.

Who is your email host? Do you use Thunderbird's Calendar feature, and where is it hosted? You can check that by going to calendar tab, right-click on the calendar list in the left pane, choosing Properties, and examining the Location.

If this is something that just recently started up, I wonder if your hosting service is either having problems or is in the process of offloading some of their services, like calendaring to another provider.

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