Urgent - Trouble uploading new leads

Urgent - Trouble uploading new leads

Hi guys,

I want to upload leads into Zoho without creating duplicates. I know this can be done two ways:
  1. Export leads from Zoho and make changes to the fields and import it back. This method would use the Record ID to identify whether to update an existing record or create a new one.
  2. Import XLS/CSV file directly without exporting first. As there is no record ID available in this case, Zoho will use the 'Email' field to identify whether to update an existing record or create a new one.
I want to use option 2 for importing data because there is a limit of 3000 records that can be exported from Zoho and I don't want to keep repeating the process for a greater number of leads. So while using method 2, here is the problem:

I am trying to update the 'Email' field itself in the records using a CSV file import. But since Zoho uses the Email field to check for duplicates, I can never update but only create new records which I don't want to do. The way I can fix this is if Zoho allows me to use some other field or fields (phone or last name + company name) to check if a record already exists or not (instead of using the Email field) and then make the change accordingly. Is this possible? Either through the Zoho CRM interface or through the API? 

This should be a standard feature. I don't see why there is a restriction on which field Zoho uses to check for duplicates. I want to upgrade to the Enterprise edition because of my expanding business but this issue is a big hurdle right now because it messes up our workflow. Look forward to your support!


Cheers,
Andre