Index: branches/5.3.x/core/install/upgrades.php
===================================================================
diff -u -N -r16324 -r16395
--- branches/5.3.x/core/install/upgrades.php	(.../upgrades.php)	(revision 16324)
+++ branches/5.3.x/core/install/upgrades.php	(.../upgrades.php)	(revision 16395)
@@ -1,6 +1,6 @@
 <?php
 /**
-* @version	$Id: upgrades.php 16324 2016-01-23 19:30:25Z alex $
+* @version	$Id: upgrades.php 16395 2016-11-12 12:43:14Z alex $
 * @package	In-Portal
 * @copyright	Copyright (C) 1997 - 2009 Intechnic. All rights reserved.
 * @license      GNU/GPL
@@ -2069,6 +2069,11 @@
 			$table_name = $config->getTableName();
 			$fields = $this->Conn->Query('DESCRIBE ' . $table_name, 'Field');
 
+			// The "_renameTables" method doesn't rename IDField, so find real one in DESCRIBE result.
+			if ( !isset($fields[$id_field]) ) {
+				$id_field = 'EventId';
+			}
+
 			if ( !isset($fields['l1_Body']) ) {
 				// column dropped - nothing to convert anymore
 				return;
@@ -2352,6 +2357,45 @@
 		}
 
 		/**
+		 * Update to 5.2.2-B1
+		 *
+		 * @param string $mode when called mode {before, after)
+		 */
+		public function Upgrade_5_2_2_B1($mode)
+		{
+			if ( $mode != 'after' ) {
+				return;
+			}
+
+			$this->deleteThumbnails();
+		}
+
+		/**
+		 * Deletes folders, containing thumbnails recursively.
+		 *
+		 * @param string $folder Folder.
+		 *
+		 * @return void
+		 */
+		protected function deleteThumbnails($folder = WRITEABLE)
+		{
+			foreach ( glob($folder . '/*', GLOB_ONLYDIR) as $sub_folder ) {
+				if ( $sub_folder === WRITEABLE . '/cache' ) {
+					continue;
+				}
+
+				if ( basename($sub_folder) === 'resized' ) {
+					$files = glob($sub_folder . '/*');
+					array_map('unlink', $files);
+					rmdir($sub_folder);
+				}
+				else {
+					$this->deleteThumbnails($sub_folder);
+				}
+			}
+		}
+
+		/**
 		 * Update to 5.3.0-B1
 		 *
 		 * @param string $mode when called mode {before, after)