I just tested what I think you were dong in Word 2010, and I don’t get the same issues. (Thanks to Tony Jollans on the Microsoft Office Word Discussion Group who alerted me to this solution: ) Continue using the shortcut key to turn highlighting on and off.This is necessary when you have a shortcut key assigned to the highlighting function - for some reason, the function is ‘sticky’ as soon as you select a new color. Click the toolbar icon to turn off the ‘sticky’ highlighter.Click on the drop-down arrow next to the toolbar icon.

Once changed, the new color applies whenever you press the shortcut key combination. The default highlight color is yellow, but you can change it.

Removing highlighting: Select the highlighted text, then press Ctrl+Alt+H.

Adding highlighting: Select the text you want to highlight, then press Ctrl+Alt+H.

In Word 2007, someone realized that a key combination for turning highlighting on and off would be a good idea, so they included one - Ctrl+Alt+H.

Save this key combination in the template (7).

If this key combination is available, displays (6).

That way, when you move to Word 2007 you won’t have to reassign the keys or remember something different. Suggestion: Use Ctrl+Alt+H, the same as Word 2007.

Put your cursor in the Press new shortcut key field (5) and press the key combination you want to assign to color highlighting.

In the Commands list on the right, scroll down to Highlight and select it (4).

On the Customize Keyboard window, select All Commands from the Categories list on the left (3).

You must do this now otherwise you can’t see the Highlight command.

Go to Tools > Customize on the Word menu, and select the Commands tab (1).

And that’s not as intuitive or as easy as you’d think because they left Highlight off the Format list! Here’s how you do it: In Word 2003 you have to assign your own keystroke combination for highlighting. It’s fine when you only have the occasional highlighting to do, but what if you’re doing a lot of adding/removing highlighting from text? You need a quicker way, right? Word 2003 Microsoft Word has a toolbar icon for applying and removing color highlighting, just like using a real highlighter.

Word for mac highlight text