web client HTTP 500 error

I've got a custom interactive app throwing HTTP 500 error when executing from the web client. It's updating a bunch of F4211 records using MBFs.

Are these errors saved? Where are these errors?

I've looked in
1. Server Manager for the given instance.
2. E1 kernel log

I've cranked up the e1 debug log and web client user log and while both explode in size, there is not reference to the http 500 error.

Odd thing is that the records appear to be updated correctly.

Any help is much appreciated.

(running web sphere 7 if that helps)

That error is thrown by your web server (websphere, in your case), when your app does something "bad" or when it perceives it as such. Check the websphere logs for details on what caused the issue. Does your interactive app take a long time to do the update?

Yes, it takes a long time to update, it's updating F4211 date fields via B4200310. Some of the orders get large and it's only on the large orders it throws the error. I'm trying to avoid using a work file and UBE but i think I might have too.

possibly relevant

Doc ID 1265515.1