Unable To Add New Article To New Category. Add article window is open, category selection menu does not show new category. It does show all other categories. Is there something I'm missing here or is there a normal delay?

Our new corporate email signature, which contains 5 images, is a requirement in all email correspondence. The problem is that when users are contacting us via help desk, the signature is applied with the images. Images are very small, 20-40kb, but do...