diff --git a/htdocs/install/check.php b/htdocs/install/check.php
index 3ba9e41c670..81a950d3f81 100644
--- a/htdocs/install/check.php
+++ b/htdocs/install/check.php
@@ -536,5 +536,5 @@ $(".runupgrade").click(function() {
 </script>';
 
 dolibarr_install_syslog("--- check: end");
-pFooter(true);	// Never display next button
+pFooter(1);	// Never display next button
 
diff --git a/htdocs/install/default.css b/htdocs/install/default.css
index c3d97cdaa74..abf9baa5a7d 100644
--- a/htdocs/install/default.css
+++ b/htdocs/install/default.css
@@ -55,6 +55,8 @@ background: #FDFDFD;
 border: 1px solid #ACBCBB;
 padding: 0 0 0 0;
 margin: 0 0 0 0;
+color: #AAA !important;
+cursor: not-allowed !important; 
 }
 
 input[type=submit] {
diff --git a/htdocs/install/inc.php b/htdocs/install/inc.php
index 0b604763737..5b010f80e0b 100644
--- a/htdocs/install/inc.php
+++ b/htdocs/install/inc.php
@@ -412,7 +412,7 @@ function pHeader($subtitle,$next,$action='set',$param='',$forcejqueryurl='')
 /**
  * Print HTML footer of install pages
  *
- * @param 	integer	$nonext				No button "Next step"
+ * @param 	integer	$nonext				1=No button "Next step", 2=Show button but disabled
  * @param	string	$setuplang			Language code
  * @param	string	$jscheckfunction	Add a javascript check function
  * @param	integer	$withpleasewait		Add also please wait tags
@@ -429,9 +429,9 @@ function pFooter($nonext=0,$setuplang='',$jscheckfunction='', $withpleasewait=0)
     print '</td></tr></table>'."\n";
     print '</td></tr></table>'."\n";
 
-    if (! $nonext)
+    if (! $nonext || ($nonext == '2'))
     {
-        print '<div class="nextbutton" id="nextbutton"><input type="submit" value="'.$langs->trans("NextStep").' ->"';
+        print '<div class="nextbutton" id="nextbutton"><input type="submit" '.($nonext == '2' ? 'disabled="disabled" title="DisabledBecauseOfErrorAddParamignoreerrors"':'').'value="'.$langs->trans("NextStep").' ->"';
         if ($jscheckfunction) print ' onClick="return '.$jscheckfunction.'();"';
         print '></div>';
         if ($withpleasewait) print '<div style="visibility: hidden;" class="pleasewait" id="pleasewait"><br>'.$langs->trans("NextStepMightLastALongTime").'<br><br><div class="blinkwait">'.$langs->trans("PleaseBePatient").'</div></div>';
diff --git a/htdocs/install/mysql/migration/3.8.0-3.9.0.sql b/htdocs/install/mysql/migration/3.8.0-3.9.0.sql
index ed7eb22c21d..e6e92a65fc7 100755
--- a/htdocs/install/mysql/migration/3.8.0-3.9.0.sql
+++ b/htdocs/install/mysql/migration/3.8.0-3.9.0.sql
@@ -26,6 +26,9 @@
 ALTER TABLE llx_don ADD COLUMN fk_country integer NOT NULL DEFAULT 0 after country;
 
 
+UPDATE llx_user set api_key = null where api_key = '';
+
+
 UPDATE llx_commande_fourn set billed=1 where statut = 8;
 UPDATE llx_commande_fourn set statut=5 where statut = 8 and billed=1;
 
diff --git a/htdocs/install/mysql/migration/repair.sql b/htdocs/install/mysql/migration/repair.sql
index 53034338932..fafe5a4ad9f 100755
--- a/htdocs/install/mysql/migration/repair.sql
+++ b/htdocs/install/mysql/migration/repair.sql
@@ -6,6 +6,9 @@
 -- Requests to clean corrupted database
 
 
+UPDATE llx_user set api_key = null where api_key = '';
+
+
 -- delete foreign key that should never exists
 ALTER TABLE llx_propal DROP FOREIGN KEY fk_propal_fk_currency;
 ALTER TABLE llx_commande DROP FOREIGN KEY fk_commande_fk_currency;
diff --git a/htdocs/install/step1.php b/htdocs/install/step1.php
index d1eca1211ba..e8bb030ed81 100644
--- a/htdocs/install/step1.php
+++ b/htdocs/install/step1.php
@@ -727,7 +727,7 @@ function jsinfo()
 
 dolibarr_install_syslog("--- step1: end");
 
-pFooter($error,$setuplang,'jsinfo',1);
+pFooter($error?1:0,$setuplang,'jsinfo',1);
 
 
 /**
diff --git a/htdocs/install/step2.php b/htdocs/install/step2.php
index 8f27aa53767..bb7e37c7e47 100644
--- a/htdocs/install/step2.php
+++ b/htdocs/install/step2.php
@@ -616,6 +616,6 @@ else
 
 dolibarr_install_syslog("--- step2: end");
 
-pFooter(!$ok,$setuplang);
+pFooter($ok?0:1,$setuplang);
 
 if (isset($db) && is_object($db)) $db->close();
diff --git a/htdocs/install/upgrade.php b/htdocs/install/upgrade.php
index b9aef70445e..4d42e225429 100644
--- a/htdocs/install/upgrade.php
+++ b/htdocs/install/upgrade.php
@@ -483,8 +483,8 @@ $ret=0;
 if (! $ok && isset($argv[1])) $ret=1;
 dol_syslog("Exit ".$ret);
 
-dolibarr_install_syslog("--- upgrade: end");
-pFooter(((! $ok && empty($_GET["ignoreerrors"])) || $dirmodule),$setuplang);
+dolibarr_install_syslog("--- upgrade: end ".((! $ok && empty($_GET["ignoreerrors"])) || $dirmodule));
+pFooter(((! $ok && empty($_GET["ignoreerrors"])) || $dirmodule)?2:0,$setuplang);
 
 if ($db->connected) $db->close();
 
diff --git a/htdocs/install/upgrade2.php b/htdocs/install/upgrade2.php
index 8729dedc0a5..60f6e082f50 100644
--- a/htdocs/install/upgrade2.php
+++ b/htdocs/install/upgrade2.php
@@ -423,7 +423,7 @@ if ($error && isset($argv[1])) $ret=1;
 dol_syslog("Exit ".$ret);
 
 dolibarr_install_syslog("--- upgrade2: end");
-pFooter($error,$setuplang);
+pFooter($error?2:0,$setuplang);
 
 if ($db->connected) $db->close();