website works through Visual studio but not through IIS

hello, i have this unusual issue with iis when i try to run my website. iis crashes due to stackover flow exception that is coming from third party dll. however, when i run the same site through visual studio it works fine (same project files and dll). cant figure out why it would not crash in visual studio. i tried to reproduce the crash through visual studio both in release mode and debug but it doesn't happen. i can not change third-party dll at all as it is read-only. i have searched on net but ppl had similar issue but in their case they were able to get rid of stackoverflow exception by modifying the code. in my case i have to use third party dll and i can not modify it. am i missing any setting in iis? thanks!