can't activate AutoCAD 2011 LT

[Anonymous]

Please help me, I using my company AutoCAD, but cannot activate using the product key.

[pendean]

You are either entering the wrong code or more than likely someone at your office already used that license number to upgrade to a newer version.
Go talk to your IT/CAD manager or boss and confirm either situation. Not much anyone here can do about it.

[Anonymous]

Hi Pen, we enter the correct lic key and we didnt upgrade to other version since the license of this autocad is good for single license only. is there a way i can activate to used the autocad lt 2011 working properly thank you

[TravisNave]

If your product was ever under Subscription and then lapsed, this could be the problem.  Autodesk 2011 products are retired.  However, if it was never upgraded or not expired under Subscription, then you may still be able to activate it. 

See this KB for more information on invalid serials:

http://knowledge.autodesk.com/support/autocad/troubleshooting/caas/sfdcarticles/sfdcarticles/Error-S...