Why would you want to use the same invoice numbers again? This can create confusion as you now have invoices with the same invoice number. If you use the invoice number as the key in a relationship, this can be a disaster.
It can be done, as a script can be used to reset the "next serial value" or you can update it manually, but this does not sound like a good idea. I'd just let the invoice numbers continue to increment year after year.
Thanks for getting back to me.
Every 'new year' I put my invoice numbers back to 1, always have done so after 10 years of business I don’t end up with invoice number 37294532.
It makes everything easier to organize witch is why I would like to be able to do it, just cant work out how to.
Seems to me that this would make things harder to organize rather than easier. Surely there's a date field on your invoice? So you can group your records by year when it's necessary?
Is this field used to link invoices to other tables?
If so, don't do it. It will scramble your data.
If it's just a data field not used to link to other tables in relationships, open manage | Database | Fields, find the field and double click it to open file options. Select the auto -enter tab and you'll find a place where the next serial value is specified. Set this value back to 1 and your next new invoice will be numbered 1 again.