How to see the actual server side error message in the browser?

I'm having a trouble reproducing an issue a user is having in IE, but something that always bugged me is how can I see the error message from classic ASP page in IE for example on a dev server.

In IE all I see is for example:

This page contains programming error

And that's it.

Note: since this is server side, it applies to all browsers.

Solution

I remember this one!

You need to go into ie settings > advanced > uncheck "show friendly http errors"

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