Try disabling the glewExperimental support, as that may be attempting to call something in OpenGL that isn't supported by your particular driver. That actual error is GL_INVALID_ENUM which, unfortunately, can be raised from pretty much anywhere.
Also, what OpenGL driver are you using and in what environment? Some drivers may allow you to enable a debug log or the like. Unfortunately, and GLEW itself may also provideis not written in a mechanism for seeing what calls are being made and what effect they have onway that makes it easy to add in generic glGetError() checks after every extension query or the like, but you might be able to narrow it down by adding it in at strategic locations.