Hi, ALL. Today for the first time I tried to build my software in Release mode. This is the command MSVC generates: /OUT:"..\dbhandler\vc_mswudll\postgres_dll.dll" /MANIFEST /NXCOMPAT /PDB:"vc_mswudll\my_dll.pdb" /DYNAMICBASE "dbinterface.lib" "libpq.lib" "kernel32.lib" "user32.lib" "gdi32.lib" "comdlg32.lib" "winspool.lib" "winmm.lib" "shell32.lib" "shlwapi.lib" "comctl32.lib" "ole32.lib" "oleaut32.lib" "uuid.lib" "rpcrt4.lib" "advapi32.lib" "version.lib" "wsock32.lib" "WS2_32.lib" "wininet.lib" "Secur32.lib" "odbc32.lib" "odbccp32.lib" /IMPLIB:"vc_mswudll\my_dll.lib" /DEBUG /DLL /MACHINE:X86 /OPT:REF /SAFESEH /INCREMENTAL:NO /PGD:"vc_mswudll\postgres.pgd" /MANIFESTUAC:"level='asInvoker' uiAccess='false'" /ManifestFile:"vc_mswudll\my_dll\postgres.dll.intermediate.manifest" /OPT:ICF /ERRORREPORT:PROMPT /NOLOGO /LIBPATH:"..\dbhandler\Release" /LIBPATH:"..\libpg\src\interfaces\libpq\Release" /LIBPATH:"C:\Program Files (x86)\Visual Leak Detector\lib\Win32" /TLBID:1 And this is what I got: 1>libpq.lib(dirmod.obj) : error LNK2001: unresolved external symbol __imp____iob_func 1>libpq.lib(win32error.obj) : error LNK2001: unresolved external symbol __imp____iob_func 1>libpq.lib(fe-connect.obj) : error LNK2001: unresolved external symbol __imp____iob_func 1>libpq.lib(snprintf.obj) : error LNK2001: unresolved external symbol __imp____iob_func 1>libpq.lib(encnames.obj) : error LNK2001: unresolved external symbol __imp____iob_func 1>libpq.lib(chklocale.obj) : error LNK2001: unresolved external symbol __imp____iob_func 1>libpq.lib(fe-exec.obj) : error LNK2019: unresolved external symbol __imp__sscanf referenced in function _pqSaveParameterStatus 1>libpq.lib(snprintf.obj) : error LNK2019: unresolved external symbol __imp__sprintf referenced in function _fmtptr 1>..\dbhandler\vc_mswudll\postgres_dll.dll : fatal error LNK1120: 3 unresolved externals 1> 2 Warning(s) 1> 9 Error(s) What am I missing? Thank you