Signtool returns error 0x800700C1 while trying to sign AutoCAD OEM 2023 setup.exe

Ok, thanks Shawn and Jens for chiming in.
I fully understand your frustration, believe me I also get frustrated over these things and the lack of feedback on error messages with the new ODIS installation concept.

Jens’ issue was solved, see this thread: How to avoid headaches when starting with AutoCAD OEM 2025

Also, Robert Green’s issue is now (partially?) solved by studying the ODIS logs. The key and quickest way to solve these issues is without doubt to use the log file collection tool announced here: Troubleshooting installation issues OEM
It’s simple and straightforward to use and most likely the fastest way to deal with installer issues.

It turns out the TOU (Terms Of Use) refer to Autodesk terms, which is not correct as an OEM product is a partner product and not an Autodesk product.

Madhukar at the ADN explains how the TOU issue is fixed here: