https://forums.autodesk.com/t5/installation-licensing-forum/installation-error-autocad-2010-lt-on-windows-8-1/m-p/5454878#M151039 <P>you can try using the windows Compatibility troubleshooter: <A href="http://windows.microsoft.com/en-us/windows/make-older-programs-run#1TC=windows-7" target="_blank">http://windows.microsoft.com/en-us/windows/make-older-programs-run#1TC=windows-7</A><BR /><BR />or you can try using a 3rd party tool called longbow: <A href="http://www.longbowsoftware.com/" target="_blank">http://www.longbowsoftware.com/</A> not free<BR /><BR />none of these are guaranteed to work<BR /><BR />Autocad LT 2010 came out years before window&nbsp;8.1 did so it will never be compatible</P> <P>also disable antivirus before installing</P> Mon, 29 Dec 2014 21:53:30 GMT DarrenP 2014-12-29T21:53:30Z