The following files had got polluted with unwanted BOMs. http://en.wikipedia.org/wiki/Byte_Order_Mark#Unwanted_BOMs radegast/Radegast/FormFlash.cs radegast/Radegast/GUI/Consoles/MapConsole.Designer.cs radegast/Radegast/GUI/Consoles/MapConsole.cs radegast/Radegast/GUI/Consoles/Assets/Notecard.Designer.cs radegast/Radegast/GUI/Consoles/Assets/Notecard.cs radegast/Radegast/GUI/Consoles/Inventory/InventoryConsole.cs radegast/Radegast/GUI/Notifications/FriendshipOfferNotification.Designer.cs radegast/Radegast/GUI/Notifications/FriendshipOfferNotification.cs radegast/Radegast/GUI/Notifications/GenericNotification.Designer.cs radegast/Radegast/GUI/Notifications/GenericNotification.cs radegast/Radegast/GUI/Notifications/GroupInvitationNotification.Designer.cs radegast/Radegast/GUI/Notifications/GroupInvitationNotification.cs radegast/Radegast/GUI/Notifications/PermissionsNotification.Designer.cs radegast/Radegast/GUI/Notifications/PermissionsNotification.cs radegast/Radegast/GUI/Notifications/ScriptDialog.Designer.cs radegast/Radegast/GUI/Notifications/ScriptDialog.cs radegast/Radegast/GUI/Notifications/TeleportNotification.Designer.cs radegast/Radegast/GUI/Notifications/TeleportNotification.cs radegast/Radegast/Properties/AssemblyInfo.cs radegast/Radegast/Properties/Settings.Designer.cs This cause build errors with nant. FormFlash.cs(31,1): error CS8025: Parsing error