I got today this error, which is brand new to me. I like to write about uncommon errors that I bump into, so here goes an explanation of what happened (btw: me very dumb! hahaha)

I am creating an ASCX control for a .Net 3.5 site. I have an all white control and wanted to have a quick UI just to do a bit of testing and prototyping without having to spend too much time working on the UI piece of things. My motto is “get it to work first, and now make it look pretty”, which is not exactly what most devs do. Most devs do “get it to work, who cares about it looking pretty”.

Anyway, I created a Master page, copy pasted directly from the web and VOILA, besides an endless set of strings and multiple forms I also got the following line in my new master page.

Just delete all references to viewstate in the copy pasted text. Do the same for forms, simplify and use the new UI

Error text:
Server Error in ‘/PaymentsWeb’ Application.

The state information is invalid for this page and might be corrupted.

Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.Web.HttpException: The state information is invalid for this page and might be corrupted.

Source Error:

[No relevant source lines]

Source File: c:\Users\xavier\AppData\Local\Temp\Temporary ASP.NET Files\paymentsweb\8e1d30e5\5e7998b7\App_Web_smihqcyt.0.cs Line: 0

Stack Trace: