The upload of new Extensions can fail for the following reasons:
Incorrect file format:
for your convenience an example file is available in the Company Panel.
e.g. an invalid email address, please make sure the email address is valid and does not contain white spaces or invalid domain extensions. Also don’t use text values in numeric fields.
e.g. a caller ID per extension is required and the number used as caller ID must be linked to the company. Note that only ‘Last name’, ‘Anonymous’ and ‘Qaller Plus’ are optional fields.
internal numbers must be unique and cannot already be in use for another Extension or Dial plan.
Furthermore, make sure the import file doesn’t include any embedded tables or hidden symbols.