By default the quota assigned to the new email accounts you create is 250MB. What if you wish to increase the default quota limit from 250MB to a higher value ?
Yes, it is possible. However, you should have root access to the server. The following option under the Mail tab within WHM >> Server Configuration >> Tweak Settings will allow you to change the default value.
Default user-defined quota value for new email accounts
Remember to ensure the option below it called “Default quota option for new email accounts” is set to “User-defined”. Note that you have to change the quota for existing email accounts manually or utilize our API to develop a script that finds all email accounts and changes their quotas.