I just downloaded the May 2009 download and now I'm getting the error message...

Multiple controls with the same ID '_header' were found. FindControl requires that controls have unique IDs.

I have no idea as to where to go with this.

Help? Ideas?

Post the HTML of your page, as well as any relevant code behind if you're creating controls dynamically.

Hi,

The problem is you are assigning the same id to 2 different controls. Please post your markup and if you're creating controls dynamically post that code also.

I don't have any controls with the ID '_header' suggesting that its AJAX related. Furthermore, when I use Build #3.0.20820.0, the page works perfectly fine.

The problem appears to be a known bug with the Accordian AJAX control. Fortunately, I had to shelve the user control with the accordian so commenting it out wasn't that big of an issue.