Hi Ryan,
A couple of questions that could make a big difference in the solution. Are you only using this to create a new ID for existing records, or do you plan on using this formula for the creation of new records as well? What is being used as the key field for the table? Also, if this was an legacy ID field, why are we checking for null? If it was an ID field, they should all have a value in them. Simply adding 3 0's would be as easy as making this field a formula text field and using this formula [Record ID#] & "000". However, if this is going to be a primary key field or is going to be used to create ID's for new records, there is a lot more set up required because you cannot base a formula on the Record ID for new records since the ID is not known until after the record is saved.
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Brandon Drake
JHI Group
Monroeville OH
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