Lead conversion mapping - changing field reference

Question

Our previous admin incorrectly set up our Accounts and Contacts to use a custom "lead_source" rather than the standard "leadsource" used in Leads. This make it impossible (for me) to map lead source when converting Leads into Accounts and Contacts. At the very least, it requires two duplicate pick fields. How can I prevent losing all of the "lead_source" information, while fixing the error for all new lead conversions? What happens to existing Accounts and Contacts if I just change the Account/Contact Form to use the standard "leadsource?"

Note, I am an end user acting as admin because we don't have one so please make replies as "for dummies" as possible. Thanks!

Answer 1

What happens to existing Accounts and Contacts if I just change the Account/Contact Form to use the standard "leadsource?"

Changing a page layout (the form) will not affect anything on the data level. The value of the picklist fields on existing Account and Contact records will remain the same, stored in that custom field on each object. As long as you don't delete the field from the object level, the data will remain.

How can I prevent losing all of the "lead_source" information, while fixing the error for all new lead conversions?

Like above, the data (values for the picklist fields) on existing Account and Contact records will remain available, even if you change the layout and start using LeadSource going forward.

I would suggest configuring Account and Contact to use leadsource the way you want them, and then running an Apex job to automatically populate the new lead source field (that you create or implement), retroactively based on the existing picklist values on the old Accounts and Contacts. If you need help with that, people here will be glad to help :)