MAC-adress verification

So Im struggeling to get this right.

Senario: In cell A1-A10 i need to check its a valid MAC adress.
Cell must only have Capital letters and letters in the cell can only be A to F and numbers 0 to 9 and it needs to be 12 numbers or letters.

If the Cell not is valid I need it to turn red.

AA0032AB3461 Is a valid cell
AA0032AB34G1 is not a valid cell since it holds a G, This cell I want to be red
aa0032ab3451 is not valid since the letters are not capital, This cell I want to be red

Been using =ISNUMBER(SUMPRODUCT(FIND(MID(A1,ROW(INDIRECT("1:"&LEN(A1))),1),"0123456789ABCDEF")))

But its not what im looking for.

In what way is the formula NOT what you are looking for? It seems to work fine on the examples you have given. Can you give some examples where it does NOT work?

Is this what you are looking for?

CF rule for A1:

=AND(A1<>"",NOT(ISNUMBER(SUMPRODUCT(FIND(MID(A1,ROW(INDIRECT("1:"&LEN(A1))),1),"0123456789ABCDEF")))))

Applies to : $A$1:$A$10

Administrative Note:

Members will tailor the solutions they offer to the version of Office (Excel) that you have. Please check that your forum profile is up-to-date in this respect. If you aren't sure, in Excel go to File | Account and report what it says below the MS logo at the top of that page. If your version is for Mac, please also state this. Thanks.

You need an extra condition in there:

=AND(A2<>"",OR(NOT(LEN(A2)=12),NOT(COUNT(FIND(MID(A2,ROW($1:$12),1),"ABCDEF0123456789"))=12)))

and FWiW, this also avoids the use of the volatile INDIRECT function.

This is a new and different question that will require either data validation or possibly VBA.

Please start a new thread with a suitably descriptive title for this.

AliGW and Glenn: what is the difference between the two?

Glenn explained this above.

If that takes care of your original question, please select Thread Tools from the menu link above and mark this thread as SOLVED.

Also, if you have not already done so, you may not be aware that you can thank those who have helped you by clicking the small star icon located in the lower left corner of the post in which the help was given. By doing so you can add to the reputation(s) of all those who offered help.

1. Ali's fromula did not exclude NON-12 character strings.

2. The INDIRECT function recalculates every time anything changes. On small sheets this is not an issue, but if there are lots of them on a big sheet... it will get slow.