Could you upload the project file here?
What's the coordinate system you are using?
I don't really see why TBC is actually utilizing the old CToolbox. Your screenshot shows that the MS990 compatibility is set to NO.
On my computer it only uses the CToolbox when MS990 is set to yes, because it needs to create a Geoid Subgrid that is stored in the .CFG file.

One other thing you can try is to use the Trimble Office Cleanup Utility from here, near the bottom of the page, even if it says 5.30 it'll work with newer versions:
https://geospatial.trimble.com/trimble-business-center-utilities-license-and-installation-support#:~:text=Trimble%20Office%20Cleanup%20Utility%20%28November%202021%29%20%E2%80%94%20This,versions%20of%20TBC%20to%20assure%20a%20clean%20installation.Uninstall and cleanup all settings that have anything to do with TBC, CToolbox, coordinate system database.
And re-install TBC, that will bring the other things back as well.