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Can't connect Anthropic "authentication failed: model: claude-sonnet-4-20250514" error

  • April 19, 2026
  • 37 replies
  • 451 views

I have my Anthropic Developer account set up with an API key and billing enabled. I keep trying to connect Anthropic to Zapier but keep getting this message. Any ideas on how to resolve this?
authentication failed: model: claude-sonnet-4-20250514

 

Best answer by SamB

Hi everyone 👋

Sorry for the delayed update here. I'm happy to report that this issue has been resolved! Our engineers have fixed the problem that was causing valid API keys to fail during authentication, so you should be able to connect your Anthropic account without any errors now.

I know this issue was super frustrating, especially for those of you setting up your first Zaps or with workflows held up for over a week. Really appreciate everyone's patience while our team worked on the fix. And thank you ​@ojvs for sharing that workaround to help get things working for folks while the fix was being worked on.

Thanks again for hanging in there, and let us know if anyone's still running into trouble 🙏

37 replies

SamB
Community Manager
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  • Community Manager
  • April 20, 2026

Hi and welcome to the Community ​@bullseyepc! 😁

I did some checking and found we’ve got a bug report open for this issue. We can’t give any estimate as to when it will be resolved by but our Support team have added you to the list of users being affected, so you’ll get an email notification from us as soon as it is.

There aren’t any workarounds noted at the moment but I’ll be sure to follow up here if I come across any. Let us know if there’s anything else I can help with in the meantime.


SamB
Community Manager
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  • Community Manager
  • April 20, 2026

Hey ​@bullseyepc, would you mind running the following quick tests to help our engineering team isolate the cause of the issue?

  1. Add a different Anthropic user account to your Zapier account and test if that connection works as expected
  2. Create a brand new connection for the existing account that’s been erroring, by going to My Apps > Add Connection, then reconnect and test again

This'll help us figure out whether the issue is with the connection itself or the account. 🙏


I am getting the same exact message as well when I try and connect my Claude API key to Zapier. I was told that it is currently being worked on.


Could you please add me as well...have same error. Thank you!

 


  • New
  • April 21, 2026

Please could you add me to the email notification too - I’m experiencing the same error. Thank you


  • New
  • April 21, 2026

@SamB I am having the same issue, tried reconnecting the account, tried a new API key, the works and got the same error. Could I also be added to the affected users list please to get an email when there might be a solve? Thank you!


  • New
  • April 21, 2026

same error


Getting the same error too! Tried so many times. Please add me to the notification list!


SamB
Community Manager
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  • Community Manager
  • April 22, 2026

Hi there ​@nick_pagliarulo, ​@DoubleDeuce22, ​@Ads, ​@ventures, ​@8blocks and ​@jaydenbowles 👋

Sorry to hear you’re all being affected by this issue too. I’ve made sure that anyone who wasn’t already added to the list by our Support team has been added now. We can't share a timeline on a fix, but you’ll all get an email notification once it's resolved.

@ventures, thanks for sharing that both reconnecting and using a new API key didn’t work. I’ll let our engineers know.

Thanks for everyone’s patience in the meantime 🙏


  • New
  • April 22, 2026

I am having the same issue please add me to the email list 


  • New
  • April 23, 2026

I’m having the same issue, can I please be added to the notification list?


SamB
Community Manager
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  • Community Manager
  • April 23, 2026

Sure thing ​@jcurr and ​@Anouska! I’ve added you both to the list now, we’ll be in touch by email once it’s been sorted.


  • New
  • April 23, 2026

I’m having a same issue. Please  add me to the mail list. I wish it will be solved in the very near future.


  • New
  • April 23, 2026

I am affected by this as well, and would like to receive an email once resolved.


  • New
  • April 24, 2026

I am getting the same error.  Please do keep me posted.  Per Claude, the error is because Zapier is trying to use a model that does not exist.  

 

The error is saying Zapier is trying to use a model that doesn't exist.

Check your Zapier Claude integration settings:

  1. In Zapier, find where you're configuring the Claude connection
  2. Look for a "Model" field
  3. Change it to one of these valid models:
    • claude-3-5-sonnet-20241022 
    • claude-3-opus-20240229
    • claude-3-haiku-20240307

  • New
  • April 24, 2026

This was literally my first workflow and I am hitting this issue. Looks like its not first time user at fault :)


SamB
Community Manager
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  • Community Manager
  • April 24, 2026

Hi ​@minsoo, ​@silkroad, ​@mully, ​@karl007 👋 

Sorry to hear you’re all being affected by this as well. I’ve added you all to the list so you’ll get an email from us as soon as it’s been fixed. Thanks for everyone’s continued patience in the meantime 🙏 


  • New
  • April 24, 2026

please could you add me Sam, this is my first workflow and i’m having issues.


Hi Sam, please add me to the list as well. I'd like to be notified when this is fixed. 


please add me to the list as well, same error showing here


  • New
  • April 25, 2026

Same error, and it is kind of a dealbreaker. It looks like this is unresolved still a week later from first post? Please add me to the list.


  • New
  • April 26, 2026

I also have the same problem and would like to get a email when the problem is fixed


  • New
  • April 26, 2026

You can take me off the notification list. I just went over to Make.com and while the setup is a little less intuitive, it works and is much cheaper.


  • New
  • April 27, 2026

please add me to the list as well, same error showing here


  • New
  • April 27, 2026

You can take me off the notification list. I just went over to Make.com and while the setup is a little less intuitive, it works and is much cheaper.

i have also been thinking about using make.com, but i have heard that zapier is the branch leader, does anyone really know what the difference is and why is zapier better?