Hi Dirk,
You are missing a comma after the second second cost code. You also don't really need the "Cost Code=""". The first condition you are testing is whether cost code is not blank, so if that is true it will return cost code. If that condition is false, (the false condition being that cost code is blank), it will return [Building Group Identifier] & [Record ID#].
So you could write it as - if the cost code is not blank, cost code, otherwise building group identifier and record id.
If([Cost Code]<>"",[Cost Code],[Building Group Identifier] & [Record ID#])
I hope that helps!
Katherine
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Katherine Carothers
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