When a database contact uses the forward to friend feature, the email address being forwarded to is stored in the database and cannot be used (by another contact for email change).
The only way to use this hidden email address is to first manually add it to the database, then change it to another random email address, then remove the contact. This action allows the original hidden email address to be used by another contact that may want to change to that address.
For example - Email Address 1 wants to change to Email Address 2. However, Email Address A forwarded an email to a friend who at some point had Email Address 2.
When you search for Email Address 2, you don't see it because its hidden behind the scenes. The only way to make email address 2 usable is to do the following.
- Add the email address to the database.
- Change it to another address, for example, change email@example.com to firstname.lastname@example.org.
- Delete email@example.com. Now the original Email Address 2 (firstname.lastname@example.org) can be used by Email Address 1.