I too am having problems with the 'Smart Guides' option being grayed out in the 'View' - 'Grids and Guides' column. I've replaced the preferences, checked all the appropriate boxes, yet nothing I do works. Additionally, the 'Smart Guides' did work for some time. However, for reason(s) I'm unaware of, they just stopped showing up. I'm stumped. Any suggestions?
I've branched your question out of the Replace Your Prefs thread into one of its own and changed the title so more people will see it. I'm not able to make the menu item go gray here, and I'm going to presume that you followed the instructions in the other thread for trashing the prefs, so I'm not going to suggest you do that again, at least not yet.
It would help if we know your OS and version of ID (including the update patch applied).
Perhaps this will help: http://indesignsecrets.com/why-is-some-feature-grayed-out-in-indesign. php
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