Tab not working on Microsoft Word 2011
I experience the problem of tabs not working when making math tests. The problem is very repeatable, and can be replicated in the following simple experiment:


Get a new document and set one tab (say a left tab at 3.0 inches). 
Type "Solve " and insert a formula, say "2x=6". 
Use the right arrow to exit from the formula. 


You may now type any non-tab characters that you wish, but hitting the "tab" key does not insert a (tab) character.

To fix the problem, do any of the following after leaving the formula:


Type (spacebar) (left arrow) (tab), OR
Paste a previously copied (tab), OR 
Click to place the cursor at any point not within the formula, and click to place the cursor at the end of the line. Now type (tab).


My theory is that a flag is set to keep the (tab) character from being used within formulas, and that exiting the formula using the right arrow key does not reset the flag, but clicking outside the formula or backspacing does.