How to know if mailbox is not full
Inside your mailbox, below the block containing all folders you can see how much free space has left. Maximum size of Inbox Mail is 20 Gb.
If a red line appears, you must clean your mailbox. Otherwise there won’t be a possibility to send or recieve messages.
Delete all unnecessary messages from all the folders and at the end – empty trash. If you need a larger mailbox look for more.
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