There is currently a known issue with mail delays where it can take many days for mail to arrive. We are working on resolving this, and have no current workaround.

Gold and items cannot be sent to another realm or faction.

Troubleshooting World of Warcraft in-game mail issues.

Items or gold left in the mailbox for too long is deleted

Item Restoration process failed to send one or more of the items selected during the self-restore process

More information on returned mail

Anglers' Water Striders disappeared from mount collection equipment slot

Troubleshooting World of Warcraft in-game mail issues.

Mail can prevent a character from being deleted.

What to do if you receive a Mechagon item container from the mail and it can't be opened.