Invalid Access Code
The older MH CD-ROM registration number you entered for your MH31 Digital Edition UPGRADE is not valid. Please recheck the number you have and try re-entering it.
Empty Registration Code, Please Enter!
This is an upgrade digital product. To purchase and use this Machinery’s Handbook 31 Digital Edition Upgrade, you must have either:
The previous edition MH CD-ROM registration number is not validating as entered. You have tried to enter it too many times.
Please write to firstname.lastname@example.org with the registration number and details of the problem you are having.