Hi @ネパリ サンデャ,
First, I'd like to confirm whether you are using the modern communication site or a Team site, this is because the SharePoint Server Publishing Infrastructure feature can’t be activated on the communication site.
Please check the following article for reference: Enable publishing feature
Notes:
- The classic publishing site templates includes the publishing features by default.
- Classic publishing features are not available on modern communication sites. Modern communication sites provide a newer alternative by default.
If you get the error enabling SharePoint server publishing infrastructure feature in modern team site, try using a different browser to see the result. Also, if there are other site admin, please contact them to get this feature activated, see if they get the same result.
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