For Revit 2021 see Autodesk Revit 2021 Content.

The solution is to access the Autodesk Revit Content web pages for your version of Revit and install the appropriate content: This issue is known to affect the UK, English (US Metric) and English-Imperial (US Imperial) content and may potentially affect that for other countries/ regions also. This will cause issues with integration and should be corrected. Users will find that several important ‘.rfa’ format files or the associated ‘.txt’ information files may be missing or contain incomplete data. Since version 2021, it appears that Autodesk have streamlined their installation and now the initial family content installed by the default installation is incomplete. For Revit 2023 use the Tekla Structural Designer Integrator for Autodesk Revit 2023 (version 23.0) released in December 2022.For Revit 2022 use the Tekla Structural Designer Integrator for Autodesk Revit© 2022 (version 8.0) released in June 2021.*This was updated to version 7.02 in June 2021 and we recommend you install this latest update also.For Revit 2021 use the Tekla Structural Designer Integrator for Autodesk Revit© 2021 (version 7.0)* released in July 2020.There is a specific version of the Integrator for each version of Revit: To integrate with Revit you can download and install the appropriate version of the Integrator for Autodesk Revit.

Revit 2023 release date