diff --git a/install/sql/incremental/upd_dev_collection.sql b/install/sql/incremental/upd_dev_collection.sql
index e69de29bb2d1d6434b8b29ae775ad8c2e48c5391..c3d8c5b210d5df66bb4e02a69368c334b69e6e58 100644
--- a/install/sql/incremental/upd_dev_collection.sql
+++ b/install/sql/incremental/upd_dev_collection.sql
@@ -0,0 +1,2 @@
+
+ALTER TABLE `mail_user` CHANGE `quota` `quota` BIGINT(20) NOT NULL DEFAULT '0';
diff --git a/install/sql/ispconfig3.sql b/install/sql/ispconfig3.sql
index cf340bda0170cb77039941455303d76ee28066ca..e9ed67c86a441cca00f6bcd898eaa92b58361725 100644
--- a/install/sql/ispconfig3.sql
+++ b/install/sql/ispconfig3.sql
@@ -1070,7 +1070,7 @@ CREATE TABLE `mail_user` (
   `gid` int(11) NOT NULL default '5000',
   `maildir` varchar(255) NOT NULL default '',
   `maildir_format` varchar(255) NOT NULL default 'maildir',
-  `quota` bigint(20) NOT NULL default '-1',
+  `quota` bigint(20) NOT NULL default '0',
   `cc` text,
   `forward_in_lda` enum('n','y') NOT NULL default 'n',
   `sender_cc` varchar(255) NOT NULL default '',
diff --git a/interface/lib/classes/quota_lib.inc.php b/interface/lib/classes/quota_lib.inc.php
index b02cdea9949fb92c23451a18f49b2377a3d23d4c..7c5b388536ec9d0a672d9a3e283d2a5d6b7adc97 100644
--- a/interface/lib/classes/quota_lib.inc.php
+++ b/interface/lib/classes/quota_lib.inc.php
@@ -326,7 +326,7 @@ class quota_lib {
 					if($used_ratio >= 0.8) $databases[$i]['display_colour'] = '#fd934f';
 					if($used_ratio >= 1) $databases[$i]['display_colour'] = '#cc0000';
 
-					if($databases[$i]['database_quota'] == 0){
+					if($databases[$i]['database_quota'] == -1) {
 						$databases[$i]['database_quota'] = $app->lng('unlimited_txt');
 					} else {
 						$databases[$i]['database_quota'] = $databases[$i]['database_quota'] . ' MB';
diff --git a/interface/web/dashboard/dashlets/templates/databasequota.htm b/interface/web/dashboard/dashlets/templates/databasequota.htm
index 082dd1f8c0dfdbdba890de2471098a540f34cfc1..4e8db908bd137575b08fcc386ac821fee57e09b8 100644
--- a/interface/web/dashboard/dashlets/templates/databasequota.htm
+++ b/interface/web/dashboard/dashlets/templates/databasequota.htm
@@ -14,7 +14,7 @@
 			  <td>{tmpl_var name='database_name'}</td>
 			  <td>{tmpl_var name='used'}</td>
 			  <td>{tmpl_var name='database_quota'}</td>
-			  {tmpl_if name="quota_raw" op="!=" value="0"}<td>
+			  {tmpl_if name="quota_raw" op="!=" value="-1"}<td>
 			  <div class='progress'>
 				  <div class='progress-bar-striped progress-bar progress-bar-{tmpl_if name="used_percentage" op="<" value="50"}success{tmpl_elseif name="used_percentage" op="<" value="75"}warning{tmpl_else}danger{/tmpl_if}' role='progressbar' aria-valuemin='0' aria-valuemax='100' aria-valuenow='{tmpl_var name="used_percentage"}' style='width: {tmpl_var name="used_percentage"}%'><span>{tmpl_var name="used_percentage"}%</span>
 				  <span class='sr-only'>{tmpl_var name='used'} {tmpl_var name='of_txt'} {tmpl_var name='database_quota'}</span>
diff --git a/interface/web/mail/form/mail_user.tform.php b/interface/web/mail/form/mail_user.tform.php
index 32e58686e28a16d312fd2884e3d3d0d1bc6e34cc..f513aeb9d3e4763f3f9947f91c9f00cba6e2d53b 100644
--- a/interface/web/mail/form/mail_user.tform.php
+++ b/interface/web/mail/form/mail_user.tform.php
@@ -166,7 +166,7 @@ $form["tabs"]['mailuser'] = array(
 					'regex' => '/^([0-9]{1,})$/',
 					'errmsg'=> 'quota_error_value'),
 			),
-			'default' => '-1',
+			'default' => '0',
 			'value'  => '',
 			'width'  => '30',
 			'maxlength' => '255'