Web.config Custom Errors mode Conflict

Question

I have a great and important problem with Web.Config, I need to see the Error of my page and resolve it in asp.net web form and web config, but when Error Occurred, I see an

Answer 1

I just wanted to comment here, but I do not have enough point to comment, Can we see the actual, page that produces the error and see the entire web.config? you can blur out the connectionstrings and such so as not to give any passwords away.

But with what I see,

I think from what you are saying you are using IIS Express debugging on local machine. I would done IIS Express, or ctrl+F5 the page to see if the site is just not cached.

setting the custom errors to Off will show you the debug message - NOTE the "O" in Off must be capitalized with lower case of the f's. looks like you have this, but worth mentioning

Custom Errors Off - Specifies that custom errors are disabled. This allows display of detailed errors.