Unable to connect Calendly, says "invalid token"

  • 21 September 2023
  • 3 replies

I’ve been trying to connect Calendly for a few days now and I keep getting an error message saying “authentication failed: The app returned ‘invalid token’.” I’d like to note that even if it failed, Calendly shows up in my list of apps albeit unusable as it says the auth has already expired and that I need to reconnect it.


3 replies

Userlevel 7
Badge +6

Hi there @CFG,

I did some digging into our notes, and it's likely you are using a v2 API Key. At the moment, the Calendly Zapier integration uses the v1 API and a v1 is required.

For the time being, I would like to suggest this workaround:

To create a v1 API key, follow these steps:

  1. Go to:
  2. Scroll down and click on Regenerate Key

    (Click here to view larger)

IMPORTANT: regenerating the v1 API Key will break all existing third-party applications connections that use it, including but not limited to Zapier. For this reason, you will need to enter the regenerated v1 API Key into any Zapier app connections and any other third-party apps that still use the v1 API Key.

Hopefully, this helps!

This isnt working anymore. Any other solutions? 

Userlevel 7
Badge +6

Hi there @trainedadvisor,

I did some digging into this, and it seems like Calendly appears that is now connects using OAuth for both authentication and authorization, which doesn’t need the use of API key to connect.

I’d recommend checking the version of the Calendly app and if you’re getting the exact same “Invalid token” error.

Hopefully, this helps.