We released AutoCAD and AutoCAD LT 2013 Service Pack 1 recently. Unfortunately a limited issue was found in the original Service Pack 1 after release, so we recalled it. We sincerely apologize for the inconvenience. There is a new AutoCAD and AutoCAD LT 2013 Service Pack 1.1 with the issue resolved and will install on any AutoCAD and AutoCAD LT 2013 with or without the original Service Pack 1 installed. AutoCAD 2013 Service Pack 1.1 AutoCAD LT 2013 Service Pack 1.1 More from the AutoCAD Support blog “Without a Net” The Return of SP1 for AutoCAD and AutoCAD LT 2013 Go to the original post...