i have a form that contains ID(combobox), name(textbox),age(textbox)
these three fields is create under db1.mdb.
example:
ID=3000
Name=john
age=20
once the user select the ID from the combo box(select 3000), when the user release the mouse, the textbox of name will automatically appear
"John", how to do this? any code is appreciate.

Simple

use the mouse up event to trigger the query
When this is fired look at the no in the text box (3000). use this as the filter for the query. Get the desired name and put into the textbox

Regards