ASPX: logins fail after adding new user until app pool is recycled

See more:

C#

ASP.NET

Hi,

This app has been in use for a couple of months now. I have made no changes to the login process which is just an asp:login.

I have recently created a new "onboarding" facility that creates a new mysql schema, restores a database and creates an admin user on both. It also calls this in an attempt to preempt the issue:

HttpRuntime.UnloadAppDomain();

A little background: The app is not open to the public. Our customers sign up their company and add employees as users. Each company has their own Tsql and MySql database.

So now, after running this onboarding, my tester creates a user account on the company, logs out of the dev account and back in as that user. After using the system as the new test user, she logs out and tries to log back in as the dev user again.

At this point all logins fail. All the users are told that their login fails. Recycle the app pool and all is fine again.

I can't reproduce the error locally, which is maddening, so I have no idea where to even start looking >_<

Any help is greatly appreciated, even if it's just an idea of how I can recreate / debug this issue.

Oh, to boot: remote debugger is just unusable. It takes 2 minutes just to F11

Thanks ^_^
Andy

PS:

What I have tried:

Tried recreating the issue locally, tried debugging the code on the server.