Add zeros (if necessary) to a number in access
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I have a table that contains employee numbers. They need to be 5 numbers long (#####). However, sometimes the data entry doesn't quite make that happen, and there are only 4 or 3. How can I ensure that all numbers are 5 digits long?

EDIT:  Sorry, forgot to mention, data entry takes place through a bank, in a different country. I have absolutely no control over how the data is presented, I only have to deal with it once it is downloaded.