Data Validation Overriding Itself?

[gmbhbls]

I have a single column. If I enter this code into the validation, It does what I want. It constrains the entries so that they start with either "PCO-R0343-" or "DVCO-R0343-".

=OR(AND(LEN(A5)=14,EXACT(LEFT(A5,10),"PCO-R0343-"),ISNUMBER(-MID(A5,ROW(INDIRECT("11:14")),1))),AND(LEN(A5)=15,EXACT(LEFT(A5,11),"DVCO-R0343-"),ISNUMBER(-MID(A5,ROW(INDIRECT("12:15")),1))))

I also have this code. If I remove all validation code and enter this code, instead, it does what I want. It constrains the entries so that the last four characters cannot be duplicated anywhere in the column.

=AND(COUNTIF($A$5:$A$1005,"*-R0343-"&RIGHT(A5,4))=1)

But, If I enter this code (the two prior codes merged together) it's as if the red code is ignored and the blue code is all that's being "enforced".

=OR(AND(LEN(A5)=14,EXACT(LEFT(A5,10),"PCO-R0343-"),ISNUMBER(-MID(A5,ROW(INDIRECT("11:14")),1))),AND(LEN(A5)=15,EXACT(LEFT(A5,11),"DVCO-R0343-"),ISNUMBER(-MID(A5,ROW(INDIRECT("12:15")),1))),AND(COUNTIF($A$5:$A$1005,"*-R0343-"&RIGHT(A5,4))=1))

Does anyone see what may be causing one formula to override the other one?

I thank you in advance for all of your time and effort!

Edit:

I am limited by the number of characters, or I would add in place of the blue code: (COUNTIF($A$5:$A$1005,"PCO-R0343-"&RIGHT(A5,4))=1) and (COUNTIF($A$5:$A$1005,"DVCO-R0343-"&RIGHT(A5,4))=1)

 

[shg]

Now you have

=OR(AND(LEN(A5)=14, EXACT(LEFT(A5, 10), "PCO-R0343-"),  ISNUMBER(-MID(A5, ROW(INDIRECT("11:14")), 1))),
    AND(LEN(A5)=15, EXACT(LEFT(A5, 11), "DVCO-R0343-"), ISNUMBER(-MID(A5, ROW(INDIRECT("12:15")), 1))),
    AND(COUNTIF($A$5:$A$1005, "*-R0343-"&RIGHT(A5, 4))=1))

I expect you want

=AND(OR(AND(LEN(A5)=14, EXACT(LEFT(A5, 10), "PCO-R0343-"),  ISNUMBER(-MID(A5, ROW(INDIRECT("11:14")), 1))),
        AND(LEN(A5)=15, EXACT(LEFT(A5, 11), "DVCO-R0343-"), ISNUMBER(-MID(A5, ROW(INDIRECT("12:15")), 1)))),
     COUNTIF($A$5:$A$1005, "*-R0343-" & RIGHT(A5, 4))=1)

 

[gmbhbls]

Thank you, shg! That's exactly what I was trying to accomplish! I appreciate your help!

Now you have

=OR(AND(LEN(A5)=14, EXACT(LEFT(A5, 10), "PCO-R0343-"),  ISNUMBER(-MID(A5, ROW(INDIRECT("11:14")), 1))),
    AND(LEN(A5)=15, EXACT(LEFT(A5, 11), "DVCO-R0343-"), ISNUMBER(-MID(A5, ROW(INDIRECT("12:15")), 1))),
    AND(COUNTIF($A$5:$A$1005, "*-R0343-"&RIGHT(A5, 4))=1))

I expect you want

=AND(OR(AND(LEN(A5)=14, EXACT(LEFT(A5, 10), "PCO-R0343-"),  ISNUMBER(-MID(A5, ROW(INDIRECT("11:14")), 1))),
        AND(LEN(A5)=15, EXACT(LEFT(A5, 11), "DVCO-R0343-"), ISNUMBER(-MID(A5, ROW(INDIRECT("12:15")), 1)))),
     COUNTIF($A$5:$A$1005, "*-R0343-" & RIGHT(A5, 4))=1)

 

[shg]

You're welcome.