Hi @Ana ,
How did you get the GUID of the default site design “Team site”?
I tried to reproduce your issue in my SharePoint tenant by using PowerShell command:
Set-SPOSiteDesign -Identity <Team site’s guid> –Title <new title>
Then I attempted to retrieve Team site’s guid as below:
As shown in the above screenshot, only the custom site designs could be retrieved, but the default ones like Team site were not retrieved, I was unable to get the GUID of the default site designs.
So I tried to search online, I found this article contains the description about retrieving the default site designs’ guids:
So I used the value of “Showcase” given by it to get the site design to check if the command could work well. However, it returned “File Not Found”:
When testing using a custom site design’s GUID, it could work well.
So, Per my test, “Set-SPOSiteDesign” seems only work for the custom Site Designs, but not for the default ones like team site, Topic, Showcase or Blank.
If I misunderstand your meaning, please feel free to reply.
I hope this information has been useful, please let me know if you still need assistance.
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