--- a/bin/installto.sh
+++ b/bin/installto.sh
@@ -38,13 +38,15 @@ if (!preg_match('/define\(.RCMAIL_VERSION.,\s*.([0-9.]+[a-z-]*)/', $iniset, $m))
 
 $oldversion = $m[1];
 
-if (version_compare(version_parse($oldversion), version_parse(RCMAIL_VERSION), '>='))
+if (version_compare(version_parse($oldversion), version_parse(RCMAIL_VERSION), '>=') && !opts['force'])  
   rcube::raise_error("Installation at target location is up-to-date!", false, true);
 
-echo "Upgrading from $oldversion. Do you want to continue? (y/N)\n";
-$input = trim(fgets(STDIN));
+if (!opts['accept']) {
+  echo "Upgrading from $oldversion. Do you want to continue? (y/N)\n";
+  $input = trim(fgets(STDIN));
+}
 
-if (strtolower($input) == 'y') {
+if ($opts['accept'] || strtolower($input) == 'y') {
   echo "Copying files to target location...";
 
   // Save a copy of original .htaccess file (#1490623)
@@ -99,7 +101,11 @@ if (strtolower($input) == 'y') {
   }
 
   echo "Running update script at target...\n";
-  system("cd $target_dir && php bin/update.sh --version=$oldversion");
+  $command = "cd $target_dir && php bin/update.sh --version=$oldversion";
+  if ($opts['accept']) {
+      $command .= " --accept";
+  }
+  system($command);
   echo "All done.\n";
 }
 else {