Allow Content Editor Web Part

At Site Settings > Site Features > Site Collection Features, you will want to have the Office SharePoint Server Publishing Infrastructure set to active.

Then, on the site, go to Site Settings > Site Features, and activate the Office SharePoint Server Publishing feature. You should then be able to add the content editor web part to the site.

Quite often I see SharePoint 2010 websites without the Content Editor webpart (MSContentEditor.dwp)

To enable this web part you need to activate the BasicWebParts feature on that site. I did not find an option to do this by the web site admin; you can enable the feature however by using SharePoint powershell.

Execute the following statement in the SharePoint Powershell and the Content editor web part will be added to your site

Enable-SPFeature 00bfea71-1c5e-4a24-b310-ba51c3eb7a57 -Url [SharepointSiteUrl]

To get the SharePoint site url just run

Get-SPSite

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