Program triggers a breakpoint when run in debugger but works if run without debugger

I created a dll and it is getting attached with a server application. Now the problem is, if I run the server from the command prompt then the dll will be running fine. But if I debug the server in visual studio then the server will crash because of dll. Then I debugged it thoroughly and got to know that it is crashing while assigning the memory. I checked evry possible thing, memory overwrite, memory leak, but everything seems to be fine. Anyone encountered this type of problem before. Why is this happening? I searched on the internet also but all I am getting is " crashing in release mode and not in debug mode". EDIT: I am getting the following message on the window: Windows has triggered a breakpoint in tcas.exe. This may be due to a corruption of the heap, which indicates a bug in tcas.exe or any of the DLLs it has loaded. This may also be due to the user pressing F12 while tcas.exe has focus. The output window may have more diagnostic information. If I click on continue, then their wont be any problem. Edit: Sorry I forgot to mention that it is the debug build I am using and not the release build.