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SendMessageNL is often the best option for a fast bulk import and email sending but users should be aware of some known limitations
- there is a fixed delay time of 20' that affects immediate sending and scheduled sending that are to be done in less than 20'. This delay is due to import process time
- temporary groups should be periodically deleted by accessing MailUp console (a temporary group has the naming convention "Automatic NN", where NN is a progressive number, and it can be deleted when sending is done)
- imported Import process time leads to a delay for immediate sending requests. Delay duration depends on the size of the file to be imported.
- Imported files should be periodically removed from admin console user space to avoid to be charged of exceeding user space
- message scheduling fails if If you specify a start date/time that occurs in the past then your request is enqueued for immediate sending.
- In some cases message scheduling could fail (e.g. when another sending is planned at specified date and time (, in this case you can use GetNewsletterQueues to retrieve available time slots before calling SendMessageNL)method call fails if import file contains duplicated email addresses. Scheduling failure is notified by email to the technical contact that is registered on MailUp admin console. An email message from support@mailup.it will then notify user when operation cannot be completed, also reporting an error code that is detailed here
- if the file to be imported contains more than one milion of recipients please contact us
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