libpq msvc crashing

Hi
Has anyone had problems running the testlibq in xp using msvc or encounterd this problem.

I am using postgresql 7.3.1, which if I run two command shell (one as a server) it works fine. I only encounter problems when I try to run msvc. I am fairly new to postgresql, so I am basically trying to get the example programs to work, so that I know that the C programme communicates with the server, however everytime the programme compiles, It crashes. A college lecturer has looked at the code and commented out a lot of the code to establish where its going wrong, to us it seems it does not like the line of code

/* make a connection to the database */
conn = PQsetdb (pghost, pgport, pgoptions, pgtty, dbName);

libpq.dll, libpq.lib and header files are included, pghost and pgport are set, we are not sure on pgoption and pgtty though, however we have simulated different scenarios and hit the same result. Compiles then CRASH, can anyone help.

Thanks

Garfield
palmer_garfield(at)hotmail(dot)com