I am using a System.Web.UI.WebControls.Menu on my site. Today I tried to move it into a master page and it all broke down.

The menu loads but appears fully expanded until it is moused over when it contracts itself.

Even when the menu has contracted itself mousing over menu items makes squares appear on the screen and shows child menu items under the wrong parent.

Viewing source shows that the most obvious thing that has changed is now all menu styles, names and ids begin with an underscore character (i.e. are prefixed with _ctl0_)

I've confirmed that this is the problem by saving the source and replacing all instances of "_ctl0" with "ctl0" and the menu works fine again.

How can I get this _ct10 (which I assume is the ClientID of the master page?) to be something compliant with HTML specifications and (more importantly for me) the menu code?

Hello Microsoft.

Any response to this issue?

Hi Martin,

Can you send me a simple example in a .zip file that shows the problem you are having?  I can then work to help you fix it.

Thanks,

Scott

It's alright I've found the problem eventually! The conversion wizard left the following tag in my web.config

Removing that means that my controls are now prefixed with ctl0 not _ctl0.

Hopefully this will help other people as I see from your blog that I'm not the only person this has happenned to!