--- a/browser/components/migration/EdgeProfileMigrator.js
+++ b/browser/components/migration/EdgeProfileMigrator.js
@@ -216,13 +216,19 @@ EdgeProfileMigrator.prototype.getResourc
  * - |[]| to indicate "There are no profiles" (on <=win8.1) which will avoid using this migrator.
  * See MigrationUtils.jsm for slightly more info on how sourceProfiles is used.
  */
 EdgeProfileMigrator.prototype.__defineGetter__("sourceProfiles", function() {
   let isWin10OrHigher = AppConstants.isPlatformAndVersionAtLeast("win", "10");
   return isWin10OrHigher ? null : [];
 });
 
+EdgeProfileMigrator.prototype.__defineGetter__("sourceLocked", function() {
+    // There is an exclusive lock on some databases. Assume they are locked for now.
+    return true;
+});
+
+
 EdgeProfileMigrator.prototype.classDescription = "Edge Profile Migrator";
 EdgeProfileMigrator.prototype.contractID = "@mozilla.org/profile/migrator;1?app=browser&type=edge";
 EdgeProfileMigrator.prototype.classID = Components.ID("{62e8834b-2d17-49f5-96ff-56344903a2ae}");
 
 this.NSGetFactory = XPCOMUtils.generateNSGetFactory([EdgeProfileMigrator]);