From reading your previous post about "deleting and substituting" some of the files, I think you've botched up TurboCAD pretty good. You need to restore your computer back before you started juggling the V7 install files and uninstall V7.
I didn't have any problems installing V7.0, but the "Update" to V7.1 is not a patch; it's a complete program install (at least the Update I have). You should place those files in a unique folder when the "TurboCADProfessional7.1Udate.exe" attempts to extract them. You need to remove Version 7 (use Add/Remove Programs in Control Panel) first, then you can use the files created by the "Update" to install (reinstall?) V7.1.
I read somewhere that IMSI/Design only supports X-amount previous versions (3-4?), beyond that, good luck! Being that V7 is 10 years old, I think you're lucky that they were willing to help.
Designer, Deluxe, (Basic, Expert, Professional), Platinum
Windows 10 Pro (1909), 64-bit