Goal Seek With Multiple Input Cells

Originally Posted by MrShorty

It will depend on the details of your Solver model. I could see trying a =COUNTIF() function somewhere in the model, then set a constraint that this COUNTIF() should be <=1. I could also see that not working very well.

Here is how I solved it. Which probably only applies to my specific problem, but I will post it any way. I used this formula in my range of input cells:

=IFERROR(INDEX($A$808:$AF$808,SMALL(IF(COUNTIF($LB807:$LQ807,$A$808:$AF$808)=0,COLUMN($A:$AF),""),COLUMNS($A:A))),"")

Since the values I get are within a specific range (1-16), I used this formula to index from values that are not in the range (17-32). Anyway, it works for me and prevents duplicates. Thanks for the help.