access dynamic combo boxes

I have a sub report that I first want to select a position and the only show the courses under that position.  I have first setup a query that shows only the positions.  then in the courses I have a query that links the positions to the courses, in that query I have added this criteria [forms]![dbo_emp_course subform]![positionSelect]  but when I select the position I am getting a enter parameter value question.  What am I doing wrong>
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When you get prompted like this it is because Access can't resolve the reference.  Usually it is a typo but in your case, if I can believe your naming convention, the control you are referencing is on a subform.  To reference a subform, you must include the mainform in the name.
So -
 [forms]![yourmainform]![dbo_emp_course subform]![positionSelect]
or in some cases, you might need -
 [forms]![yourmainform].Form![dbo_emp_course subform]![positionSelect]
Rey Obrero (Capricorn1)Commented:
you are probably looking for cascading Combo box

and this one cascading combo demo
sharris_glascolAuthor Commented:
I have it so I don't get error message now but it won't let me select an option nor is it updating list
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I just posted a sample database a few minutes ago.  It includes cascading combos so it may help you.
sharris_glascolAuthor Commented:
Ok I got it to work...  BUT in my sub report it is updating a table so when I start with the first line and select my first combo position and then select my courses it filters correctly.  when I go to do an additional line and select a different position my course on the first line goes away.  is this because of the after update that I have on the positionselect_combo?
OK.  Cascading combos in a continuous subform are a different problem.  I've attached yet another sample that explains the problem and offers a solution.  Keep in mind that this solution ONLY works for continuous view.  It will not work for DataSheet view since DS view doesn't allow controls to overlay one another.

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sharris_glascolAuthor Commented:
Thanks for all the help
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Microsoft Access

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