Have a look at the numbering format of your normal style (or whatever style
you are using for text). My guess would be that you have somehow picked up a
numbering format that is applying the indent (probably with the actual
number set to "none"). Since indents from Numbering override those from
Paragraph, that would explain why it keeps coming back.
Check also that you don't have your style set to Automatically Update
(uncheck checkbox on Style Modify dialog) and that the "Automatically update
document styles" box is off (uncheck checkbox in Tools > Templates and
Add-ins).

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Margaret Aldis - Microsoft Word MVP
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Word MVP FAQ site: http://www.word.mvps.org
> All of a sudden, Word has been automatically changing all of my paragraph
> indentations to 'hanging'. It doesn't matter how often I go to 'Format >
> Paragraph > Indents and Spacing > and change 'Special' to (none) and hit
> 'OK'; the next time I type the paragraphs indent. I go back to the same
> boxes and (none) has changed to 'hanging'. HELP!