Every time I launch TF2 it has to validate?

[Frontrox]

Did you install it on an external HD?

[Ad Bot]

[Elecro]

Did you install it on an external HD?

It was on my old hard drive and then I converted it to the new one.

[Mulch]

Ignore what everyone else says reinstalling is the simplest way.

[ShadowZero]

I had this problem, the only way I could fix it is by completely uninstalling TF2 and the reinstalling it.
It took me the whole day but it was worth it.


TLDR;Delete the TF2 Folder and Reinstall TF2.

[Frontrox]

It was on my old hard drive and then I converted it to the new one.

Should probably just reinstall