How can I redirect internal emails sent to "employee@gmail.com" so they instead go to "employee@company.com"?

How can I redirect internal emails sent to "employee@gmail.com" so they instead go to "employee@company.com"?

Our company recently hired someone full-time who had been a contractor.  As they were a contractor, they used a personal email account.  Many people accidently send to that account, and our employee doesn't get the message.  I am running Exchange 2010 in Hybrid mode with 365 (all mailboxes are on 365).
heisensteinAsked:
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Sebastian TalmonSystem Engineer Datacenter SolutionsCommented:
add gmail.com as a accepted domain in your Exchange Server (as relay domain, as your exchange is not authorative for this domain)
Then you can add his gmail address as additional mail address to his mailbox

https://docs.microsoft.com/en-us/exchange/mail-flow/accepted-domains/accepted-domains?view=exchserver-2016

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heisensteinAuthor Commented:
This worked!  Just had to set it up as an Internal Relay.
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