Team Fortress 2 spy help

[Hurley_2002]

The last couple days I been playing tf2 and anytime I select the spy class and hit number 5 on the keyboard for the disguise list to come up nothing happens. When I would look in the item option where you would go to change a weapon or what not for your class I would select the spy to change his stuff and the disguise kit is not even in there. Only the gun, knife, watch and sapper. Anyone have any ideas on how to fix this?

 

[Yakk]

I would start by validating, and possibly fixing, the game files by the Steam client.

 

[mas]

could be you connected to a modded server without realising it, which somehow screwed up your kit, just delete the mod cache and validate your base files.

 

[Hurley_2002]

How do I validate?