data validation

[chef]

I am trying to fathom out best way to approach data input issue

I can auto populate with an employee number a whole range of metrics with lookup but it has to be in a certain format and I want an data validaton pop up saying incorrect format if not input correctly

All employee numbers start with a T..does not matter lower/uppercase
It is then followed by 7 numbers although the very last digit can be alpha on occasions

so I am looking to ensure T1234567 or T123456X for example is the only format accepted so a T..6 numbers ..followed by a number or alpha for last digit

hope makes sense and maybe I cant see wood for trees trying to fathom out.
regards

sorry..this is cells column A and down to row 14500

 

[njimack]

Try this custom Data Validation formula:
=AND(UPPER(LEFT(A1))="T",LEN(A1)=8,NOT(ISERROR(MID(A1,2,6)+0)))

 

[chef]

Neil
Thank you so much for quick reply and solution..worked perfect and I would never have fathomed that out

many thanks for the help