diff --git a/emailcommon/src/com/android/emailcommon/service/SyncWindow.java b/emailcommon/src/com/android/emailcommon/service/SyncWindow.java
index c3658e369..8dfe4ad2e 100644
--- a/emailcommon/src/com/android/emailcommon/service/SyncWindow.java
+++ b/emailcommon/src/com/android/emailcommon/service/SyncWindow.java
@@ -18,7 +18,7 @@ package com.android.emailcommon.service;
 
 public class SyncWindow {
     public static final int SYNC_WINDOW_USER = -1;
-    public static final int SYNC_WINDOW_UNKNOWN = 0;
+    public static final int SYNC_WINDOW_ACCOUNT = 0;
     public static final int SYNC_WINDOW_1_DAY = 1;
     public static final int SYNC_WINDOW_3_DAYS = 2;
     public static final int SYNC_WINDOW_1_WEEK = 3;
@@ -40,7 +40,7 @@ public class SyncWindow {
                 return 30;
             case SYNC_WINDOW_ALL:
                 return 365*10;
-            case SYNC_WINDOW_UNKNOWN:
+            case SYNC_WINDOW_ACCOUNT:
             default:
                 return 14;
         }
diff --git a/src/com/android/email/provider/DBHelper.java b/src/com/android/email/provider/DBHelper.java
index 626b55554..1a9e5de6e 100644
--- a/src/com/android/email/provider/DBHelper.java
+++ b/src/com/android/email/provider/DBHelper.java
@@ -1041,11 +1041,16 @@ public final class DBHelper {
 
                 // Fix invalid syncLookback values.
                 db.execSQL("update " + Account.TABLE_NAME + " set " + AccountColumns.SYNC_LOOKBACK
-                        + "=null where " + AccountColumns.SYNC_LOOKBACK +"<"
-                        + SyncWindow.SYNC_WINDOW_1_DAY);
+                        + "=" + SyncWindow.SYNC_WINDOW_1_WEEK + " where "
+                        + AccountColumns.SYNC_LOOKBACK + " is null or "
+                        + AccountColumns.SYNC_LOOKBACK + "<" + SyncWindow.SYNC_WINDOW_1_DAY + " or "
+                        + AccountColumns.SYNC_LOOKBACK + ">" + SyncWindow.SYNC_WINDOW_ALL);
+
                 db.execSQL("update " + Mailbox.TABLE_NAME + " set " + MailboxColumns.SYNC_LOOKBACK
-                        + "=null where " + MailboxColumns.SYNC_LOOKBACK + "<"
-                        + SyncWindow.SYNC_WINDOW_1_DAY);
+                        + "=" + SyncWindow.SYNC_WINDOW_ACCOUNT + " where "
+                        + MailboxColumns.SYNC_LOOKBACK + " is null or "
+                        + MailboxColumns.SYNC_LOOKBACK + "<" + SyncWindow.SYNC_WINDOW_1_DAY + " or "
+                        + MailboxColumns.SYNC_LOOKBACK + ">" + SyncWindow.SYNC_WINDOW_ALL);
                 oldVersion = 110;
             }
             if (oldVersion == 110) {