=IF(ISNA(VLOOKUP(E15,customers!$A$1:$B$300,2,0))," yourmessage here"


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Don Guillett
Microsoft MVP Excel
SalesAid Software

"Finance Guru" wrote in message
...
Hi All,

I am using Excel 2007.

My Question is this :-

The below function checks whether the account number entered by the user
in
E15 is valid. If it is it displays,it displays the customer name in F15.

How can i amend this function to show that if an account number is not
valid
( ie. not found by the lookup function) in F15 the message is displayed
thus
' Account number not valid,please try again ', instead as it does now F15
remains blank until a valid account number is entered in E15.

All assistance greatfully accepted.

=IF(ISNA(VLOOKUP(E15,customers!$A$1:$B$300,2,0)),"
",VLOOKUP(E15,customers!$A$1:$B$300,2,0))

FinanceGuru
--
Wales - the land of fire breathing dragons and rugby playing wizards.