I have similar problem with TCP. I noticed I get "too old" message every time I run it so I wondered how often it gets old. So I go to Telerik Account, download new one and run so called TelerikControlPanelSetup_2016_3_0616_1.exe. It unpacks, then logs in and I update my packages.
Then I installed another version of VS and wanted to rerun TCP to properly install Telerik extensions there. I got same "too old" message. Then I noticed this "setup" does not install TCP, just unpacks it in TEMP and runs it. Leaving old version located in Program Files directory intact.
So I uninstalled old TCP via Programs and features and run new setup again. Guess what...same result.
What am I supposed to do to have it properly installed. For now, I just copied it from TEMP to some permanent directory and run it from there. But it's not preferred solution.