pBuffer Initialization

I have a problem when initializing pbuffers. In my Draw() method, even though I don't enable, disable or render to pbuffer, all my polygons are rendered black if I initialize the pbuffer. I don't know why this happens. If I remove the initialization from the code, I get the colors. Here's my pbufferInit() method:

BOOL pbufferInit (int width, int height)
{
	wglGetExtensionsStringARB = (PFNWGLGETEXTENSIONSSTRINGARBPROC)wglGetProcAddress("wglGetExtensionsStringARB");
        wglMakeContextCurrentARB = (PFNWGLMAKECONTEXTCURRENTARBPROC)wglGetProcAddress("wglMakeContextCurrentARB");
	wglChoosePixelFormatARB = (PFNWGLCHOOSEPIXELFORMATARBPROC)wglGetProcAddress("wglChoosePixelFormatARB");
	wglCreatePbufferARB = (PFNWGLCREATEPBUFFERARBPROC)wglGetProcAddress("wglCreatePbufferARB");
	wglDestroyPbufferARB = (PFNWGLDESTROYPBUFFERARBPROC)wglGetProcAddress("wglDestroyPbufferARB");
	wglGetPbufferDCARB = (PFNWGLGETPBUFFERDCARBPROC)wglGetProcAddress("wglGetPbufferDCARB");
	wglReleasePbufferDCARB = (PFNWGLRELEASEPBUFFERDCARBPROC)wglGetProcAddress("wglReleasePbufferDCARB");
	wglQueryPbufferARB = (PFNWGLQUERYPBUFFERARBPROC)wglGetProcAddress("wglQueryPbufferARB");
	wglBindTexImageARB = (PFNWGLBINDTEXIMAGEARBPROC)wglGetProcAddress("wglBindTexImageARB");
	wglReleaseTexImageARB = (PFNWGLRELEASETEXIMAGEARBPROC)wglGetProcAddress("wglReleaseTexImageARB");
	wglSetPbufferAttribARB = (PFNWGLSETPBUFFERATTRIBARBPROC)wglGetProcAddress("wglSetPbufferAttribARB");

	if (pbufferInitialized)
	{
		pbufferDestroy();
	}
	pbufferWidth = width;
	pbufferHeight = height;

	GLubyte *extensionString = (GLubyte *)wglGetExtensionsStringARB(wglGetCurrentDC());

	hGLDC = wglGetCurrentDC();
	hGLRC = wglGetCurrentContext();

	if (hGLDC == NULL)
	{
		MessageBox(NULL, "Error : Unable to get Current Device Context", "Context Error", MB_OK);
		return(false);
	}

	if (hGLRC == NULL)
	{
		MessageBox(NULL, "Error: unable to get GL Render Context", "Context Error", MB_OK);
		return(false);
	}

	int attr[] =
	{
		WGL_SUPPORT_OPENGL_ARB, TRUE,			// pbuffer will be used with gl
		WGL_DRAW_TO_PBUFFER_ARB, TRUE,			// enable render to pbuffer
		WGL_BIND_TO_TEXTURE_RGBA_ARB, TRUE,		// pbuffer will be used as a texture
		WGL_RED_BITS_ARB, 8,					// at least 8 bits for RED channel
		WGL_GREEN_BITS_ARB, 8,					// at least 8 bits for GREEN channel
		WGL_BLUE_BITS_ARB, 8,					// at least 8 bits for BLUE channel
		WGL_ALPHA_BITS_ARB, 8,					// at least 8 bits for ALPHA channel
		WGL_DEPTH_BITS_ARB, 24,					// at least 24 bits for depth buffer
		WGL_DOUBLE_BUFFER_ARB, FALSE,			// we don't require double buffering
		WGL_PIXEL_TYPE_ARB, WGL_TYPE_RGBA_ARB,
		0										// zero terminates the list
	};

	// choose a pixel format that meets our minimum requirements
	unsigned int count = 0;
	int pixelFormat=0;
	
	wglChoosePixelFormatARB(hGLDC,(const int*)attr, NULL, 1,&pixelFormat,&count);
	
	if(count == 0)
	{
		MessageBox(NULL, "P-buffer Error: Unable to find an acceptable pixel format", "Context Error", MB_OK);
		return(false);
	}

	// set some pbuffer attributes so that we can use this pbuffer as a
	// 2D RGBA texture target

	int pAttrib[] =
	{
		WGL_TEXTURE_FORMAT_ARB, // our pbuffer will have texture format RGBA
		WGL_TEXTURE_RGBA_ARB,
		WGL_TEXTURE_TARGET_ARB, // of texture type GL_TEXTURE_2D
		WGL_TEXTURE_2D_ARB,
		0						// zero terminates the list
	};

	// allocate the pbuffer
	hPBuffer = wglCreatePbufferARB(hGLDC, pixelFormat, width, height, (const int*)pAttrib);
	hPBufferDC = wglGetPbufferDCARB(hPBuffer);
	hPBufferRC = wglCreateContext(hPBufferDC);

	if(!hPBuffer)
	{
		MessageBox(NULL, "P-buffer Error: Unable to create P-buffer", "Context Error", MB_OK);
		return(false);
	}

	glGenTextures( 1, &pbufferTextureID );
	glBindTexture( GL_TEXTURE_2D, pbufferTextureID );
	glTexImage2D( GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE,0);
	glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER,GL_LINEAR );
	glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER,GL_LINEAR );

	pbufferInitialized = true;
	return TRUE;
}

Does anyone have an idea of why this happens? Thank you, Sriram

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