I have the doubt, if the customer is blank, should count or not?
As in the following example customer 16236154
Try:
<b></b><br /><br /><table border="1" cellspacing="0" style="font-family:Calibri,Arial; font-size:11pt; background-color:#ffffff; "> <colgroup><col style="font-weight:bold; width:30px; " /><col style="width:122px;" /><col style="width:62px;" /><col style="width:62px;" /></colgroup><tr style="background-color:#cacaca; text-align:center; font-weight:bold; font-size:8pt; "><td > </td><td >A</td><td >B</td><td >C</td></tr><tr style="height:18px ;" ><td style="font-size:8pt; background-color:#cacaca; text-align:center; " >1</td><td style="background-color:#ffff00; font-weight:bold; text-align:center; ">Customer Number</td><td style="background-color:#ffff00; font-weight:bold; text-align:center; ">Status</td><td style="background-color:#ffff00; font-weight:bold; text-align:center; ">Result</td></tr><tr style="height:18px ;" ><td style="font-size:8pt; background-color:#cacaca; text-align:center; " >2</td><td style="text-align:right; ">16236154</td><td >Ordered</td><td >Yes</td></tr><tr style="height:18px ;" ><td style="font-size:8pt; background-color:#cacaca; text-align:center; " >3</td><td style="text-align:right; ">16236154</td><td >Ordered</td><td >Yes</td></tr><tr style="height:18px ;" ><td style="font-size:8pt; background-color:#cacaca; text-align:center; " >4</td><td style="text-align:right; ">16236154</td><td > </td><td >No</td></tr><tr style="height:18px ;" ><td style="font-size:8pt; background-color:#cacaca; text-align:center; " >5</td><td style="text-align:right; ">16236154</td><td > </td><td >No</td></tr><tr style="height:18px ;" ><td style="font-size:8pt; background-color:#cacaca; text-align:center; " >6</td><td style="text-align:right; ">16236154</td><td >Ordering</td><td >Yes</td></tr><tr style="height:18px ;" ><td style="font-size:8pt; background-color:#cacaca; text-align:center; " >7</td><td style="text-align:right; ">16236154</td><td > </td><td >No</td></tr><tr style="height:18px ;" ><td style="font-size:8pt; background-color:#cacaca; text-align:center; " >8</td><td style="text-align:right; ">16236154</td><td > </td><td >No</td></tr><tr style="height:18px ;" ><td style="font-size:8pt; background-color:#cacaca; text-align:center; " >9</td><td style="text-align:right; ">32374</td><td >Ordering</td><td >No</td></tr><tr style="height:18px ;" ><td style="font-size:8pt; background-color:#cacaca; text-align:center; " >10</td><td style="text-align:right; ">32374</td><td >Ordering</td><td >No</td></tr><tr style="height:18px ;" ><td style="font-size:8pt; background-color:#cacaca; text-align:center; " >11</td><td style="text-align:right; ">32374</td><td >Ordering</td><td >No</td></tr><tr style="height:18px ;" ><td style="font-size:8pt; background-color:#cacaca; text-align:center; " >12</td><td style="text-align:right; ">32374</td><td >Ordering</td><td >No</td></tr><tr style="height:18px ;" ><td style="font-size:8pt; background-color:#cacaca; text-align:center; " >13</td><td style="text-align:right; ">37918</td><td >Ordering</td><td >No</td></tr><tr style="height:18px ;" ><td style="font-size:8pt; background-color:#cacaca; text-align:center; " >14</td><td style="text-align:right; ">37918</td><td >Ordering</td><td >No</td></tr><tr style="height:18px ;" ><td style="font-size:8pt; background-color:#cacaca; text-align:center; " >15</td><td style="text-align:right; ">10962</td><td >Ordering</td><td >Yes</td></tr><tr style="height:18px ;" ><td style="font-size:8pt; background-color:#cacaca; text-align:center; " >16</td><td style="text-align:right; ">10962</td><td >Ordering</td><td >Yes</td></tr><tr style="height:18px ;" ><td style="font-size:8pt; background-color:#cacaca; text-align:center; " >17</td><td style="text-align:right; ">10962</td><td >Ordering</td><td >Yes</td></tr><tr style="height:18px ;" ><td style="font-size:8pt; background-color:#cacaca; text-align:center; " >18</td><td style="text-align:right; ">10962</td><td >Ordering</td><td >Yes</td></tr><tr style="height:18px ;" ><td style="font-size:8pt; background-color:#cacaca; text-align:center; " >19</td><td style="text-align:right; ">10962</td><td >Ordering</td><td >Yes</td></tr><tr style="height:18px ;" ><td style="font-size:8pt; background-color:#cacaca; text-align:center; " >20</td><td style="text-align:right; ">10962</td><td >Ordering</td><td >Yes</td></tr><tr style="height:18px ;" ><td style="font-size:8pt; background-color:#cacaca; text-align:center; " >21</td><td style="text-align:right; ">10962</td><td >Ordered</td><td >Yes</td></tr><tr style="height:18px ;" ><td style="font-size:8pt; background-color:#cacaca; text-align:center; " >22</td><td style="text-align:right; ">10962</td><td >Ordered</td><td >Yes</td></tr><tr style="height:18px ;" ><td style="font-size:8pt; background-color:#cacaca; text-align:center; " >23</td><td style="text-align:right; ">90601358</td><td > </td><td >No</td></tr><tr style="height:18px ;" ><td style="font-size:8pt; background-color:#cacaca; text-align:center; " >24</td><td style="text-align:right; ">90601358</td><td > </td><td >No</td></tr><tr style="height:18px ;" ><td style="font-size:8pt; background-color:#cacaca; text-align:center; " >25</td><td style="text-align:right; ">90601358</td><td > </td><td >No</td></tr><tr style="height:18px ;" ><td style="font-size:8pt; background-color:#cacaca; text-align:center; " >26</td><td style="text-align:right; ">90601358</td><td > </td><td >No</td></tr><tr style="height:18px ;" ><td style="font-size:8pt; background-color:#cacaca; text-align:center; " >27</td><td style="text-align:right; ">90601358</td><td > </td><td >No</td></tr></table><br /><table style="font-family:Arial; font-size:10pt; border-style: groove ;border-color:#00ff00;background-color:#fffcf9; color:#000000; "><tr><td ><b></b></td></tr><tr><td ><table border = "1" cellspacing="0" cellpadding="2" style="font-family:Arial; font-size:9pt;"><tr style="background-color:#cacaca; font-size:10pt;"><td >Cell</td><td >Formula</td></tr><tr><td >C2</td><td >=IF(AND(B2<>"",COUNTIFS($A$2:$A$27,A2,$B$2:$B$27,"<>"&"",$B$2:$B$27,"<>"&B2)>0),"Yes","No")</td></tr></table></td></tr></table> <br /><br />