How to raise the quota for email?
How to increase the quota for mail?
Only by changing the tariff plan to a more optimal one in terms of parameters.
You can see the list of current tariffs at the link: https://mirohost.net/en
What to do if the mailbox is full?
Delete unnecessary irrelevant letters, including from the Trash, and contact the hosting technical support to recalculate the quota.
If deleting letters is impossible - switch to a higher tariff
How to avoid blocking mail due to exceeding the volume?
Follow the terms of use of the Mirohost public server or switch to the Dedicated server + Smart admin panel tariff so that the hosting technical support can set personalized settings for you.
Is it possible to limit the size of mailboxes?
It is not possible to limit the size of a specific mailbox. In the "Site Statistics → Site Resources" section, you can see the total space already occupied by your mail. And in the "Mail Management → Mailboxes" section of the MiroHost control panel, you can see the size of each individual mailbox.