Wikipedia, even to those with years of editing here, can always throw up some surprises and situations for which there is no obvious answer. Finding a way through all the policies, guidelines and opinions can be daunting. This is my own opinion as to how to deal with an unfamiliar situation.

Avoiding the obvious

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  1. If another editor reverts your edit with an edit summary or a note on your talkpage with a link to a policy or other page, follow the link. That at least will give you an indication of why they think they've done that, or point you to an exception which they may have missed.
  2. Don't be afraid to discuss the issue with other editors; it's courteous to approach the other editor first for some explanation, and s/he should explain more fully; however, it will soon become clear from your edit history and attitude whether you are trolling, and so don't expect to be taken seriously if you are. If you act in good faith, you will be treated with good faith.
  3. Independent advice is always available at the various versions of the Village Pump, and response is usually quite rapid.
  4. Don't rush to the Admin noticeboards for help; resources are scarce here, and generally reserved for cases needing Admin input, and in the case of WP:ANI, those needing immediate Admin input. In particular, disputes over content are not dealt with unless they involve breaches of Wikipedia's editing policies requiring consideration of sanctions such as blocking or page protection.
  5. More specifically, protection of pages against vandalism is dealt with here, current vandalism from a specific editor here, and edit-warring here. Disputes over the reliability of sources used in articles have a noticeboard here, and libel or unsourced biographical data here.