Before you import
Where to import
In Zoom, open the webinar in the web portal and click Import from CSV under Manage Attendees. The file is email, first name and last name, in columns A, B and C. Guest Manager imports from the event's Imports section and maps any columns it doesn't recognise on a Map your data screen. Zuddl imports from its attendee page using its own template.
Common errors and their fixes
Zoom has no Import from CSV button
Cause: Zoom only offers Import from CSV on single-occurrence webinars, on Pro, Business, Education or Enterprise accounts with the Zoom Webinars add-on. Recurring webinars, and webinars charging a registration fee through PayPal, don't have it.
Fix: Schedule the session as a single-occurrence webinar (one per date, if it repeats), and turn off the PayPal fee if you're importing people who've already paid.
Zoom registrants in the wrong columns
Cause: Zoom reads the file by position: column A is the email, B the first name and C the last name. Its own sample file has no header row, and an extra column or a different order puts names where emails should be.
Fix: Keep exactly three columns in that order, and delete the header line before uploading so it can't be read as a registrant.
Imported registrants are asked to register again
Cause: If the webinar's registration form has other required questions, such as company or job title, Zoom redirects imported registrants to the registration page to answer them before they can join.
Fix: Make those questions optional before importing, or ask only for what you're importing.
The Zoom file is too big
Cause: Zoom takes a CSV of up to 2MB.
Fix: Split a very large list into several files and import each one. At three columns, 2MB is tens of thousands of registrants.
Excel files won't upload
Cause: Guest Manager imports CSV files saved as UTF-8, not Excel workbooks. Zoom and Zuddl import CSV too.
Fix: In Excel, save as CSV UTF-8 (Comma delimited). In Google Sheets, download as Comma-separated values.
A guest list import is waiting for approval
Cause: Guest Manager imports of more than 100 rows need an approved account, and so does emailing tickets on import.
Fix: Ask Guest Manager to approve the account before the event, not on the day.
Duplicate guests or contacts
Cause: A Guest Manager contact's email must be unique: the same email on two rows links both to one person. Zuddl matches attendees by email too. Lists merged from several planners often have the same guest twice.
Fix: Give each guest their own row and email, and put the rest of a party in the Guests column instead. The duplicate rows guide shows how to find repeats before importing.
Extra ticket types or lists appear
Cause: Guest Manager matches Ticket Type and List by name, and a name that doesn't match creates a new one. VIP, V.I.P. and vip from three different spreadsheets become three ticket types.
Fix: Copy ticket type and list names from the event, and use the same spelling on every row.
A row with a barcode and a quantity fails
Cause: In Guest Manager, a Quantity above 1 creates several tickets, so it can't be combined with a single Barcode.
Fix: Use one row per pre-printed ticket with its barcode, or a quantity with the barcode left blank.
Countries and states not recognised
Cause: Guest Manager takes Country and State as two-letter codes, such as US and NY, not names.
Fix: Replace country and state names with their codes before importing: find and replace each one once for the whole column.
Answers land in a new field, not your question
Cause: In Guest Manager, a column fills an existing ticket question only when its header matches the question's name exactly, including capitals. Any other header creates a new custom field. In Zuddl, the template's headers must not be renamed, and session choices can't be imported.
Fix: Copy question names into the headers exactly, and map anything else on the import screen, or choose Do not import.
Tickets weren't emailed
Cause: Guest Manager only emails tickets on import when a Send Email column says Yes, the row has an email, and the account is approved to send.
Fix: Add Send Email with Yes on the rows that should get tickets, and leave it out entirely to import quietly.
Zuddl rejects the whole file
Cause: Zuddl needs the email, first name and last name for every attendee, a file under 4MB and at most 10,000 attendees per import, and caps bulk registrations at 15,000 per event. Dates and times must be in the event's time zone. A file that breaks the rules fails entirely.
Fix: Fill in the three required columns on every row, split large lists, and open the import log from the status email to see each error.
After importing
When a Zoom import finishes, the View Registrants window lists everyone imported as approved, and each of them is emailed a confirmation. Check the count against your file, and look for anyone whose name shows in the email column. Guest Manager runs imports in the background: open the import's results to check them, and revert it from there if it went wrong, which deletes the records it created.
Zuddl emails a status report with a link to the import logs, where a partial import lists the optional fields that failed. Whichever tool you use, test with two or three rows first, then import the rest, and do it days before the event rather than at the door.
Checklist before you import
Collecting registrants or guest lists from others?
Send sponsors, partners and planners a form instead of a spreadsheet. The Zoom webinar registrants template keeps Zoom's three columns in order and checks every email, and the event guest list template flags repeated guests, odd quantities and country names before you import.
Try the event guest list templateRelevant Templates
Import Builder is an independent product and is not affiliated with, endorsed by, or sponsored by Zoom, Guest Manager or Zuddl. Their names are trademarks of their owners. Import rules as described in each platform's help centre, October 2026.