It's fine that we have discussed our feelings.
Now we can move on together!
I would always be very carefull saying that, because when it comes to computers, the slightest little detail can make a difference.
Do you have a working system now? What did you use?
See if you can reproduce this error message. I have done it again and again. I wish I could show you a screen shot. The Microsoft dialog box with the little yellow triangle having an exclamation point inside it reads exactly this:
"You may not use references to other worksheets or workbooks for Data Validation criteria."
what could be more clear than that?
Now, how did I get that?
1. go to Help, press F1
2. search for these words exactly "validation list"
3. select "create drop-down list from a range of cells"
4. skip down in the instructions to where it reads
"2. If you want to use another worksheet or another workbook, do one of the following:"
5. within that section, go down to where it reads
"Use a different worksheet in a different workbook Type the list on that worksheet, and then define a name with an external reference to the list." because that is exactly what I want to do
6. now, expand the +How? link
7. actually, there is no issue there...I think we can all agree how to do the steps 1-8 and define a validation list
8. continue on down to where the steps for creating a drop-down list continue at "3. select the cell where you want the drop-down list"
9. note: this is where the problem occurs...more precisely, at step number 6. which reads:
"To specify the location of the list of valid entries, do one of the following:
If the list is in the current worksheet, enter a reference to your list in the Source box.
If the list is on a different worksheet in the same workbook or a different workbook, enter the name that you defined for your list in the Source box.
In both cases, make sure that the reference or name is preceded with an equal sign (=). For example, enter =ValidDepts.
10. OK, by the way, the statement that in both cases you need to precede the name with an equal sign is false. You do not need to add it. It is redundant. If it works at all, it will work either with the reference name "ValidDepts" or "=ValidDepts."
11. In the case that your validation list is located in the same workbook, it works.
12. But, create a separate workbook, even within the same instance of Excel, and try to reference the list in the other workbook, whether you include or exclude the equal sign, you should be able to reproduce my referenced error message.