Incorrect content type

Question

I have a document library, that has two content types on SP 2016

1. OOTB
2. Custom

Custom is set as the default content type, as well as the only available content type, using Mange Content type.

If I upload a particular document, it uses the OOTB content type.

If I fix the document using File > Info > Check for issues > Check for issues and remove "Document properties and Personal information" & "Custom XML data" the custom content type is used.

Anyone experienced anything like this. Any way to avoid saving the OOTB content type and always save custom content type

Answer 1

Can you reproduce this issue if you upload other documents, or create new documents?

Is this document created from an earlier version of Office (such as Word 97-2003 Templates) or using other templates that are not docx?

--

By default, if we have only one custom content type in this document library, there will be no other option for the library to select for you.

Based on your description, it is possible that you are uploading a document that has content type information written as hidden data and personal information, which is causing incompatibility issue.

Here is another post that provides some information about Custom XML Data, which should not be a cause to this problem.