I'd like to, but the header still contains information that I am contractually obligated not to share. I did however find a solution. If I copy and paste a header from secondary document into the original header, it allows me to edit it after that. It is still a strange problem.

Some background, the document was sent off for translation and the translators may have used a different version of Word to complete the task. I'm assuming it is some kind of corruption issue. Just a thought. Anyways, thanks for taking the time to respond, but I have found a workaround.