use boolean varaible to indicate if the user enter correct value for each input like this
If Val(employeeid_txt.Text) > 10 Or Val(employeeid_txt.Text) < 1 Then
MessageBox.Show("Employee Id Outwith Range 1 to 10 ", "Please re-enter", MessageBoxButtons.OK)
Else
correct_EmployeeID=true
End If
then if all inputs for user are correct , store that entry to your array
if correct_EmployeeID and correct_firstname and correct_surname and correct_gender and correct_position then
EmployeeRec(Index).Employeeid = employeeid_txt.Text
etc ..etc
End if
other thing about your code , your validation based on test the length of the user's input
and that not correct , I can enter something like "abcd" and your program will accept it in the gender input , it is better to compare the user's input string with "male" or "female"
and much better to make user
select the gender , and position (
use radio button). about the error messages , what if user make more than one error ! many messages will show and that will be annoying , use labels to show the error messages
If Val(employeeid_txt.Text) > 10 Or Val(employeeid_txt.Text) < 1 Then
lable_error_id.text="Employee Id Outwith Range 1 to 10 , Please re-enter" Else
correct_EmployeeID=true
End If