Before attempting to resolve the issue, it is important to first determine the cause or probable cause of the issue, so that a plan of action can be developed. In this case, the fact that the retention policy was updated shortly before users first noticed the issue suggests that this could be the cause of the issue. The systems administrator should investigate this further to determine if this is indeed the cause of the email server issue.

In a private cloud model, the cloud infrastructure is maintained within a company's own data center and is used exclusively by that company. Private clouds offer the advantage of maintaining access even when a local internet outage occurs, since the cloud infrastructure is not dependent on a public network connection.
Software as a Service (SaaS) is a cloud model in which software applications are hosted by a third-party provider and made available to customers over the internet. SaaS is not designed to maintain access in the event of a local internet outage.
A community cloud is a shared infrastructure that is used by multiple organizations, typically from the same industry or with similar requirements. Community clouds are not designed to maintain access in the event of a local internet outage.
A public cloud is a cloud infrastructure that is maintained by a third-party provider and is made available to the public over the internet. Public clouds are not designed to maintain access in the event of a local internet outage.

Dot Matrix printers do not use heat, they use a pin striking an inked ribbon (for the first copy, the subsequent copies are handled by the carbon paper)