How to change preferred communication method for internal candidates

Summary:

How to change preferred communication method for internal candidates to email

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Hello,

Does anyone know how to change the preferred communication method for internal candidates to email? At the moment, all internal candidates have the following message displayed on their record:

The candidate can't receive any emails because email isn't set as their preferred communication channel.

Does anyone know why this issue is occurring in the first place?

I raised an SR with support but they won't deal with it as it's a 'how to' question apparently.

Many thanks

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