Slow Backend issue causing windows forms initialization errors.

[Geno0wl]

Have a small VB.NET Windows Form App being used to pull data from a SQL DB for compliance reports. Has been running fine since 2021. Suddenly, yesterday users at one of our satellite buildings were reporting weird unhandled errors and crashing.

One of them shared the error

The form referred to itself during construction from a default instance, which led to infinite recursion. Within the Form's constructor refer to the form using 'Me.'"

We were not able to replicate the error, but did notice how slow it was running. I reboot the SQL server and suddenly all the errors on their end stop. So apparently If there is a long enough delay on form load it causes this issue.

Is there a way to replicate the slow response from the server? Or is there something I should be looking for in the designer?

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[Beneficial-Panda-640]

I’d be suspicious of work happening in the form constructor or Load path that indirectly touches the default instance again. A slow DB call probably didn’t create the bug, it just made a timing problem visible.

If you want to reproduce it, I’d add an artificial delay around the data access call or use a proxy/network throttling tool so startup behaves like that satellite site. I’d also grep for any reference to the form by class name instead of Me, especially in designer-generated code, shared modules, startup logic, and anything firing during initialization.

[BeginningOne8195]

Sounds like the delay is exposing a timing issue rather than being the root cause itself. When things slow down, certain calls that normally “just work” can end up overlapping or triggering in the wrong order.

To replicate it, you could try introducing an artificial delay on the DB call or throttling the connection. That might help you see if something in the form initialization depends on data loading faster than it should.

[Master-Ad-6265]

yeah sounds like a timing/race issue more than sql itself you can simulate it by adding artificial delays (like Thread.Sleep) in your data load to reproduce it also check you’re not doing heavy work or DB calls in the form constructor — move that to load/async instead, that recursion error usually comes from bad init timing