Knowledgebase: General Information
iPhone "another device is in use" error message

Using an iPhone to access your GMS Cloud email service,  you may experience an error  "another device is in use".

The “another device is in use” error will only occur on an iPhone if you are trying to access using POP3 – POP3 is an exclusive access protocol and so cannot open a mailbox that is being accessed already.

If an Outlook client or another email client is accessing your mailbox,  it will prevent your iPhone from accessing via POP3.    To resolve this you need to remove your POP3 account from your iPhone and recreate it as an IMAP account.

IMAP is designed for multiple client access and is also more efficient so this change will be beneficial.

(13 votes)
This article was helpful
This article was not helpful