Canon imagePROGRAF PRO-6600 Online Manual page 821

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Cause
Communication with mail server failed.
What to Do
Tap OK on the touch screen to dismiss the error.
Check that the receiving account and password are correctly configured in the Remote UI mail server
settings.
Setting Mail Server
If this does not resolve the error, check the status of the mail server.
Contact the mail server administrator to check the server settings and status.
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