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The domain validation (DCV) is valid for one year. Domains have to be revalidated  to continue to issue certficates for them. The earliest time a revalidation can be done is 30 days before the expiration date. To revalidate a domain, follow the same steps as above from item 5.

Note: if a domain has validation status Validated but does not show a DCV Expiration date, it needs to be validated again. Follow the same steps as above from item 5.

See below under Notifications about adding that for DCV Expiration.

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