View History only shows up if the template is modified.

(Or maybe you are on a different version of vb than I am, I have no idea when that was added... it wasn't in 3.0.12, but it is in 3.6.8)

sorry lynne i cant found view history in admincp.
in style manager and my template cant found.

Go into Style Manager -> Edit Templates -> HIGHLIGHT the Template You Want -> To the RIGHT click "View Original".

okay im found and try that.but problem not solved. :(

Of course not, you need to revert that template (assumption; I'd probably backup your style/templates first and foremost).

yes i know friend.template revert but problem not solved.
i dont know why

Can you confirm that you have disabled all plugins?

Usually if you are having problems like this (can't click on things that should be clickable), it is either the templates or a javascript conflict. You should disable your plugins and comment out any newly added javascript in your templates.

Have you confirmed that, if you switch back to Default Style, that you can use the drop-downs, etc?

You can change your view style by going into AdminCP, going to Style Manager, and clicking on the text "Default Style".

yes sure thats done,but not for my style problem.

its done like i said before.

lynne all plugin disable like i said before.im using
define('DISABLE_HOOKS', true);
in config.php for disable all plugin.thats right?

yeah,all plugin disable : im using this

but problem not solved.