I have a program which has been included the GDI32.lib and Comdlg32.lib. A class in the program uses the function of them. When running in normal mode, there is no problem. But when running in windows Service mode, when opening several instance, The program crashed. After the test we found that when we removed the code about these two library, the program is ok. Can any body tell me what's the problem? We are using VC6.0 and in 2000 and XP platform