The Restore function recovers your site files from a backup of your choice. The restore function is useful in cases where you have unintentionally removed directories or files from a domain account.
Noting that your problem is with connection, rather than missing files or having accidentally deleted a domain folder, I think the process you want would be:
Panel > Domains > Manage Domains
- Click Edit next to the troubled domain.
- Scroll down and click Change Settings
This procedure will refresh the internals over at DreamHost and (hopefully!) restore your ability to connect to your remote site without the need to trouble Support about it.
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