Consider the following scenario:
You create or import a term set in SharePoint Online.
You create or modify a Content Type in the list or in the Content Type Hub to include 10 or more Managed Metadata columns by using the managed metadata from the term set.
You add an item to the list or library.
You browse to the settings for the list or library in order to save it as a template, and then you select the option to Include Content.
When you click OK, you receive the following error message:
_catalogs/lt/<name of the list>.stp
NOTE: The <name of the list> placeholder represents the actual name of the list in which you experience the issue.
Additionally, you may encounter this issue if you have any combination of 10 or more Managed Metadata columns in your list or library. For example, assume you're using a Content Type that contains 9 Managed Metadata columns, and you add an additional Managed Metadata column to the list or library. This triggers the error.
To work around this issue, save the template without selecting the option to Include Content. Or limit the number of Managed Metadata columns in a list or library that you want to create a template from to fewer than 10.
This issue occurs because the list view threshold enforces a limit of 10 Managed Metadata columns for a list or library in SharePoint Online.
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