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[Bug]: Unable to connect to Google Calendar - Error 400: redirect_uri_mismatch #2316
Description
Bug Description
When trying to connect with Google Calendar I get following error:
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Error 400: redirect_uri_mismatch
I saw it was reported one day, but author said it was on his side - while nothing he said was working for me and Full Calendar Remastered was able to connect to Google account, so there is something wrong...
Alternatively, maybe TN could provide sign to Google button like Full Calendar Remastered does? I like FCR, but use TaskNotes much more :)
Steps to Reproduce
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Affected Task Frontmatter
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Activity
TomaszGaweda commentedon Sep 10, 2026
ok, got it working.
It needs an OAuth key of type "web application" AND to add those addresses to allowed:
http://127.0.0.1:8080?flowName=GeneralOAuthFlow
http://127.0.0.1:8080
Never got it working with only one of those, idk why. But now works... So the only thing author can do is to improve docs and specify, that those addresses are mandatory
callumalpass commentedon Sep 13, 2026
Thanks for following up, @TomaszGaweda. I'm glad you got a connection working. I don't want to document those two URLs as mandatory: TaskNotes sends a loopback redirect without a
flowNamequery parameter, and the callback port is dynamic. A Web application client with a fixed 8080 redirect is therefore not a reliable setup across connection attempts; the pending OAuth hardening also lets the OS allocate the port.I've added troubleshooting documentation to the next-release candidate explaining the supported Desktop app client setup and distinguishing
redirect_uri_mismatchfrom testing-mode403 access_denied.Could you share your TaskNotes/Obsidian versions, OS, and—if you can retest with a Desktop app client—only the
redirect_urifrom Google's error details if it still fails? Please do not share the full authorization URL, client secret, code, state, tokens, or exported settings. I'll leave this open rather than assume the original Desktop-client failure is resolved.TomaszGaweda commentedon Sep 14, 2026
Thanks @callumalpass, actually this PR is very informative and gives a necessary heads-up. I'm closing this issue as I think PR addresses it.