diff --git a/interface/ri_install.py b/interface/ri_install.py
index 97a3dbc..f43ffcd 100644
--- a/interface/ri_install.py
+++ b/interface/ri_install.py
@@ -24,27 +24,27 @@ import os.path
 import ri_data
 
 def install_over(ret):
-	if ri_oper.Rate.value == 100 and ret == 0:
-		if display.set_task_over():
-			print "reboot ..."
-			os.system("reboot")
-		else:
-			display.root_destroy()
+    if ri_oper.Rate.value == 100 and ret == 0:
+        if display.set_task_over():
+            print "reboot ..."
+            os.system("reboot")
+        else:
+            display.root_destroy()
 
 def main():
-	global has_run
-	if has_run: return
-	has_run = True
-	for instance in oper_list:
-		ret = instance.install()
-		if ret:
-			display.error(instance, ret)
-			break
-		else:
-			ri_oper.display_sub_operation((ri_oper.language=='chinese' \
-						and instance.chinese_name or instance.english_name)+\
-						(ri_oper.language=='chinese' and u' 成功\n' or ' success\n'))
-	install_over(ret)
+    global has_run
+    if has_run: return
+    has_run = True
+    for instance in oper_list:
+        ret = instance.install()
+        if ret:
+            display.error(instance, ret)
+            break
+        else:
+            ri_oper.display_sub_operation((ri_oper.language=='chinese' \
+                        and instance.chinese_name or instance.english_name)+\
+                        (ri_oper.language=='chinese' and u' 成功\n' or ' success\n'))
+    install_over(ret)
 
 has_run = False
 
@@ -52,28 +52,28 @@ def print_usages():
     print 'Usages: %s [-l|--language language] [-d|--display display-mode] [install_xml_file]' %sys.argv[0]
 
 try:
-	opts, args = getopt.getopt(sys.argv[1:], "l:d:", ["language=", "display="])
+    opts, args = getopt.getopt(sys.argv[1:], "l:d:", ["language=", "display="])
 except getopt.GetoptError:
-	print_usages()
-	sys.exit(1)
+    print_usages()
+    sys.exit(1)
 
 if len(args)>0:
-	ri_data.install_xml = args[0]
+    ri_data.install_xml = args[0]
 
 #ri_data.install_xml default value is set in ri_data.py
 if os.path.isfile(ri_data.install_xml):
-	ri_data.init_from_xml()
+    ri_data.init_from_xml()
 else:
-	print 'error: install xml(%s) does not exist' %ri_data.install_xml
-	sys.exit(1)
+    print 'error: install xml(%s) does not exist' %ri_data.install_xml
+    sys.exit(1)
 
 ri_oper.language='english'
 disp = 'ri_inst_cli'
 for opt,arg in opts:
-	if opt in ("-l","--language"):
-		ri_oper.language=arg.lower()
-	elif opt in ("-d", "--display"):
-		disp = 'ri_inst_%s' %arg.lower()
+    if opt in ("-l","--language"):
+        ri_oper.language=arg.lower()
+    elif opt in ("-d", "--display"):
+        disp = 'ri_inst_%s' %arg.lower()
 exec 'import %s as display' %disp
 
 ri_oper.display_operation     = display.set_task