diff --git a/src/wp-admin/includes/file.php b/src/wp-admin/includes/file.php
index 323789029b..f5457a56ec 100644
--- a/src/wp-admin/includes/file.php
+++ b/src/wp-admin/includes/file.php
@@ -645,7 +645,7 @@ function _unzip_file_ziparchive($file, $to, $needed_dirs = array() ) {
 	// Create those directories if need be:
 	foreach ( $needed_dirs as $_dir ) {
 		if ( ! $wp_filesystem->mkdir($_dir, FS_CHMOD_DIR) && ! $wp_filesystem->is_dir($_dir) ) // Only check to see if the Dir exists upon creation failure. Less I/O this way.
-			return new WP_Error( 'mkdir_failed_ziparchive', __( 'Could not create directory.' ), $_dir );
+			return new WP_Error( 'mkdir_failed_ziparchive', __( 'Could not create directory.' ), substr( $_dir, strlen( $to ) ) );
 	}
 	unset($needed_dirs);
 
@@ -664,7 +664,7 @@ function _unzip_file_ziparchive($file, $to, $needed_dirs = array() ) {
 			return new WP_Error( 'extract_failed_ziparchive', __( 'Could not extract file from archive.' ), $info['name'] );
 
 		if ( ! $wp_filesystem->put_contents( $to . $info['name'], $contents, FS_CHMOD_FILE) )
-			return new WP_Error( 'copy_failed_ziparchive', __( 'Could not copy file.' ), $to . $info['name'] );
+			return new WP_Error( 'copy_failed_ziparchive', __( 'Could not copy file.' ), $info['name'] );
 	}
 
 	$z->close();
@@ -744,8 +744,8 @@ function _unzip_file_pclzip($file, $to, $needed_dirs = array()) {
 
 	// Create those directories if need be:
 	foreach ( $needed_dirs as $_dir ) {
-		if ( ! $wp_filesystem->mkdir($_dir, FS_CHMOD_DIR) && ! $wp_filesystem->is_dir($_dir) ) // Only check to see if the dir exists upon creation failure. Less I/O this way.
-			return new WP_Error( 'mkdir_failed_pclzip', __( 'Could not create directory.' ), $_dir );
+		// if ( ! $wp_filesystem->mkdir($_dir, FS_CHMOD_DIR) && ! $wp_filesystem->is_dir($_dir) ) // Only check to see if the dir exists upon creation failure. Less I/O this way.
+			return new WP_Error( 'mkdir_failed_pclzip', __( 'Could not create directory.' ), substr( $_dir, strlen( $to ) ) );
 	}
 	unset($needed_dirs);
 
@@ -758,7 +758,7 @@ function _unzip_file_pclzip($file, $to, $needed_dirs = array()) {
 			continue;
 
 		if ( ! $wp_filesystem->put_contents( $to . $file['filename'], $file['content'], FS_CHMOD_FILE) )
-			return new WP_Error( 'copy_failed_pclzip', __( 'Could not copy file.' ), $to . $file['filename'] );
+			return new WP_Error( 'copy_failed_pclzip', __( 'Could not copy file.' ), $file['filename'] );
 	}
 	return true;
 }
diff --git a/src/wp-admin/includes/update-core.php b/src/wp-admin/includes/update-core.php
index c7097dc9f0..50ecafae1d 100644
--- a/src/wp-admin/includes/update-core.php
+++ b/src/wp-admin/includes/update-core.php
@@ -716,6 +716,8 @@ function update_core($from, $to) {
 	apply_filters( 'update_feedback', __( 'Copying the required files…' ) );
 	// Copy new versions of WP files into place.
 	$result = _copy_dir( $from . $distro, $to, $skip );
+	if ( is_wp_error( $result ) )
+		$result = new WP_Error( $result->get_error_code(), $result->get_error_message(), substr( $result->get_error_data(), strlen( $to ) ) );
 
 	// Check to make sure everything copied correctly, ignoring the contents of wp-content
 	$skip = array( 'wp-content' );
@@ -744,11 +746,11 @@ function update_core($from, $to) {
 		// Unlikely to be hit due to the check in unzip_file().
 		$available_space = disk_free_space( ABSPATH );
 		if ( $available_space && $total_size >= $available_space ) {
-			$result = new WP_Error( 'disk_full', __( 'There is not enough free disk space to complete the update.' ), $to );
+			$result = new WP_Error( 'disk_full', __( 'There is not enough free disk space to complete the update.' ) );
 		} else {
 			$result = _copy_dir( $from . $distro, $to, $skip );
 			if ( is_wp_error( $result ) )
-				$result = new WP_Error( $result->get_error_code() . '_retry', $result->get_error_message(), $result->get_error_data() );
+				$result = new WP_Error( $result->get_error_code() . '_retry', $result->get_error_message(), substr( $result->get_error_data(), strlen( $to ) ) );
 		}
 	}
 
@@ -770,7 +772,7 @@ function update_core($from, $to) {
 			if ( $wp_lang_dir ) {
 				$result = copy_dir($from . $distro . 'wp-content/languages/', $wp_lang_dir);
 				if ( is_wp_error( $result ) )
-					$result = new WP_Error( $result->get_error_code() . '_languages', $result->get_error_message(), $result->get_error_data() );
+					$result = new WP_Error( $result->get_error_code() . '_languages', $result->get_error_message(), substr( $result->get_error_data(), strlen( $wp_lang_dir ) ) );
 			}
 		}
 	}
@@ -820,7 +822,7 @@ function update_core($from, $to) {
 					if ( is_wp_error( $_result ) ) {
 						if ( ! is_wp_error( $result ) )
 							$result = new WP_Error;
-						$result->add( $_result->get_error_code() . "_$type", $_result->get_error_message(), $_result->get_error_data() );
+						$result->add( $_result->get_error_code() . "_$type", $_result->get_error_message(), substr( $_result->get_error_data(), strlen( $dest ) ) );
 					}
 				}
 			}