I've got a column where the entries are checked against all fields of a column on another worksheet. If there's no match the entry is invalid and colored red. This is accomplished by means of Conditional Formatting:

=EN(AANTAL.ALS(Referentie_Lijst;C5)=0;NIET(ISLEEG(C5)))
I've also written a macro which does the checking, but for ALL entry fields of that column; not just the one which was just entered. The reason for this was that I did some testing with the sheet. At some point I had so many test values that I simply selected them all and pressed [del]. To my surprise the Conditional Formatting for the fields of that particular column was deleted as well.

Is there a real problem as I got a macro which takes care of things at the end by checking them all by means of a button? Well, the people who will be using the sheet for entry wish for the immediate check per entry.

Is there a way by means of a macro or so to ensure that the Conditional Formatting is "re-applied" or something in case it gets deleted? Or should I resort to an all-macro solution? An all-macro solution would be possible to make, but I just want to know if the Conditional Formatting for a column can be locked or reapplied somehow.