What browser are you using? Are there in plugins in the browser, such as noscript plugin for Firefox, that can cause this issue?
A good way to check if you are using other browsers, is to try it in the stock browser than comes with your operating system. Assuming you have not made any changes to it (as you are using another browser), see if that works. If so, it is most likely a plugin in the browser you are regularly using.
It's not a virus. It's most likely one of the following:
* You did not upload the admin CP javascript files
* You've got an addon blocking javascript
The former seems more appropriate.