Creating inheritance users from base asp.net identity user

I have problem in which i would like to create N, two in the example, user objects (e.g. Customer & Supplier) which all inherent from the asp.net IdentityUser object. These object have very different additional data besides the the data from the IdentityUser. I would like to use the IdentityUser user as this gives me a flexible way of taking care of authentication and authorization.

Why won’t my form post back after validation?

I have an asp.net page with multiple validation summaries setup with ShowMessageBox="True" and several validators. I have run into a situation where when validation fails the validation summary displays correctly but then the next click that would normally trigger a postback of the page does not trigger a postback. So the steps look like this: