Autocad LT 2010 serial No. Problem

[Anonymous]

Dear ,

I want know why my Autocad LT 2010 activation show below error message

"The serial number you entered is not valid. Try again. (1)"

Got any solution? 

[AcadAdamLT]

Because your serial number for that product doesn't match or is invalid.

Are you sure your serial nr is for that product your trying to activate?

Are you on a subscription? if so go to subscription center, contract administrator and see if your using the correct serial nr.

Last alternative is to contact your reseller and see what they can do.