Problems with an extension

So I am developing a custom extension and I am having a issue. I have a header file that I need included in the project. If I #include the header file everything compiles and makes just fine, but after restarting the web server the extension won't load. If I remove or comment out the #include of the header file everything still compiles and makes just fine, and after restarting the web server the extension is loaded just fine. Does anyone have any idea what would cause the extension to refuse to load with the header file included? -Eric