Word works with page setups and styles. All your content is formatted according to the page setup + style + any local formatting applied.

So the first thing to check is whether there is any local formatting. On a PC you remove local formatting by selecting (Ctrl-A), then pressing Ctrl-Space and Ctrl-Q. I can't tell you the equivalent commands on the Mac but it is likely to be similar.

Next, you can check individual paragraphs to ensure their styles are all sitting on the left margin. Alternatively, you could set every paragraph to use a style that has zero left indent. We can't see your document but it is likely the style 'Normal' would have this setting.

Finally, you can change the page setup of the entire document to have whatever left margin you prefer.

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Andrew Lockton
Chrysalis Design, Melbourne Australia