Customers often call our support line asking:  "How do I prepare an Excel spreadsheet to be uploaded to CallFire?".    Here's an easy receipe to get rid of bad records that could cause upload problems:

1. Copy your phone numbers into Column-A, using Excel.   
2. Sort your list in Excel, by Column-A.   
3. Visually scan Column-A for bad numbers that have less than 10 digits, more than 10 digits, odd characters & so forth.  Delete the row enti