As most of you probably know, proper nouns are names of things, like England, Hannah, Liberal Democrats, King George etc. For my three examples, these words are likely to be in the Microsoft Word dictionary, so should not need double checking, as typos such as ‘Hanah’ would be flagged. The real danger is when you’re using less common proper nouns, such as ‘Ofsted’ or ‘Nagpur’. Both of these are real examples I have found misspelt in people’s work. Ofsted, misspelt as ‘Ofstead’ was in a document of my own, and Nagpur as ‘Napur’ in my partner’s final project.
If your document has a lot of references, and some of the authors have uncommon surnames, this is very likely to be a problem.
My best tip is to simply type a list of your uncommon proper nouns, spelt correctly, and add them to your Word dictionary, by right clicking (or going into spell check) and clicking ‘add to dictionary’. A quick Google search should tell you the correct spelling of terms you’re not sure of. For text in a document made in a programme without an inbuilt spellcheck, paste your text into word first to iron out any problems.