New/Current Leads and Salesforce

[Anonymous]

We are creating a form on a new landing page and we have a question on the form titled, “How Did You Hear About Us?” This field we want to track for this particular event within Marketo. For existing Leads/Contacts we would use an existing field in Salesforce.com as the Lead Source. How can we ensure that the existing leads do not have this information changed in Salesforce.com? Is there still a way to track what these existing Leads/Contacts selected within Marketo for this particular landing page? We’ve done some research via the Community and we were told that we can change the settings in Admin to have this field overwritten…we are having issues changing it in Admin.
 
Also, for New Leads/Contacts, we would have it sync to Lead Source within Salesforce.com. I’d like to avoid creating a new field in Salesforce.com. How do we do this?
 

[Josh_Hill13]

Colleen,

I'm a bit confused as to which fields we're talking about.

If you only want to use Lead Source, that's already synced to Marketo/SFDC.

You can field block Lead Source from being overwritten by subsequent forms with the Admin > Field Management > Field Blocking tool. There are tons of instructions on this already. Just drag in LEad Source to the center of the screen, select Field Blocking from the menu, then select the Import Sources you want to block. Usually you block Import List, Form Fill Out, etc.

This should ensure brand new leads are assigned a Lead Source while future form fill outs do not overwrite this.

[Anonymous]

Hi,

I have a form that says how did you hear about this event which will fill in their lead source field when syncing into Salesforce- i don't want existing salesforces leads who enter the form to have their specific lead source overwritten..

i went to admin-field management but it says i cannot edit this field so im confused how i go about doing this?

[Anonymous]

Josh's suggestion should work,

When in field management be careful that you are no trying to block field updated to a field called "lead source" that is in the opportunity info folder.

The field from which you want to block updates is called "Source" and is in the Lead Info folder.