Power Automate Flow returns "HTTP Error 503. The service is unavailable." and the Flow fails

[Mabel]

Hello,

I have several flows which work mostly with SharePoint API.
Usually I use "Get item", "Update item" and "Send an HTTP request to SharePoint" actions.

Most of the time everything works as it should. However, sometimes actions fail seemingly because SharePoint Online server becomes unavailable.
In this case, "HTTP error 503" is clearly indicated, but the action itself displays "Status Code: 400" and the request cannot be automatically retried.

Could you kindly explain the actual failure reason and improve the flow?

Thank you!

[CFernandes · Accepted solution]

Hey @Mabel 

I see that you are passing the path - Can you please pass the List Name\Title -

_api/web/lists/GetByTitle('ListName')

or just use the List GUID -

/_api/web/lists(guid'{list_guid}')

You can find the list GUID see - https://nickgrattan.wordpress.com/2008/04/29/finding-the-id-guid-for-a-sharepoint-list/ 

If this reply has answered your question or solved your issue, please mark this question as answered. Answered questions helps users in the future who may have the same issue or question quickly find a resolution via search. If you liked my response, please consider giving it a thumbs up. THANKS!

[Mabel]

Hi @CFernandes 

Thanks for your message.

---

I see that you are passing the path - Can you please pass the List Name\Title -

_api/web/lists/GetByTitle('ListName')

---

Yeah, that's exactly what I used.

My computer is a Japanese system. It's a SharePoint list, named "郵便・宅配便　到着通知".
After I translated the page into English in the browser, '・' became to ‘/’ .

I use "Send an HTTP request to SharePoint" to update data in the SharePoint list.

---

or just use the List GUID -

/_api/web/lists(guid'{list_guid}')

You can find the list GUID see - https://nickgrattan.wordpress.com/2008/04/29/finding-the-id-guid-for-a-sharepoint-list/ 

---

Thanks for your advice.
I will try to use this method.

[CFernandes]

@Mabel Please try using the List GUID instead.

If this reply has answered your question or solved your issue, please mark this question as answered. Answered questions helps users in the future who may have the same issue or question quickly find a resolution via search. If you liked my response, please consider giving it a thumbs up. THANKS!

[Mabel]

Hi @CFernandes 

Okay, Thanks for your proposal!
I will try to use this method to improve my flow.