Autodesk has developed the AutoCAD Security Hotfix on this page for Autodesk AutoCAD, AutoCAD LT, AutoCAD - based vertical products, and other AutoCAD - based products, to address the Heartbleed vulnerability. Please see the Readme file o. AutoCAD & AutoCAD LT All- in- One Desk Reference For Dummies ( For Dummies ( Computer/ Tech) ) by David Byrnes and Lee Ambrosius 3. 5 out of 5 stars 9. When launching AutoCAD LT the software will freeze on checking license This issue can often be caused by Anti- virus software such as Norton, or Mcafee. The Anti- virus software will often block or prevent the license manager from opening the activation window to allow a user to enter their license. The integrations are now available for all AutoCAD subscribers using Microsoft, Box, and Dropbox. Learn more about the AutoCAD web app. Download AutoCAD Today. Ready to explore these exciting new features? The innovations mentioned above are not only available with AutoCAD, but also with AutoCAD LT.