I've installed Visual Web Developer 2010 Express on a Windows XP Pro PC.  IIS is NOT installed yet. I am just evaluating this now, and the built in web server works fine for now.
I've followed these very basic steps and I'm stuck with this error:
Error WebForm_PostBackOptions is undefined
I am trying to add a RequiredFieldsValidator control to the page. Here are the steps I followed...
1- Menu options:  File -> New Web Site
2- ASP.NET Empty Web Site
3- Website -> Add new item
4- Select Web Form with Place Code in separate file checked. Master page not checked.
5- No changes to the web.config file
6- I added a couple text boxes and labels to the page and a button.
7- If I click the button now, no problem.  The page submits and is displayed with the information entered in the text box fields.
8- Add a RequiredFieldsValidator next to the ...

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