yogi_Apply Data Validation To Cell B4 So That No More Than Specified Number Of Items Can Be Selected

                      Google Spreadsheet   Post  #1750
Yogi Anand, D.Eng, P.E.      ANAND Enterprises LLC -- Rochester Hills MI     www.energyefficientbuild.com.   Sep-03-2014
post by JKL5:
(https://productforums.google.com/forum/utm_medium=email&utm_source=ba_notification#!category-topic/docs/spreadsheets/wp7kGZCPZTA)
is there a way to limit the number of times an item is entered?

Hi there, 

I'm wondering if there is any way to limit the number of times a given entry can be entered in a range. 

In this specific case I have column A showing 10 different articles and then column B which allows a user to select articles by entering an X (I have applied data validation to column X so it only allows X or blank). 

Now I want to set the limit of Xs to 5 and prevent users from entering any more Xs after that. 

The best I have been able to do so far is to put a COUNTIF on an adjacent cell, which will show a warning when more than 5 Xs have been selected, but it doesn't really prevent users from marking more articles if they really want to.

I hope I have managed to express my problem clearly. Thanks in advance for any replies! :)

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