Since this is a user to user forum, not Adobe support, you might want to try Adobe chat
Select a reason, then click I STILL NEED HELP to activate Premiere Elements chat
What computer operation system is your Premiere Elements 10 running on? For now and in the following I am assuming some version of Windows. Please confirm computer operating system.
Serial number invalid is strictly in the province of Adobe and we are not Adobe. But, let us see what the possibilities are for getting this resolve.
Contact Adobe via its Adobe Chat Serial Number Issues or Activating My Product
Click on the following link
After it opens, click on the statement "I still need help." to bring up the Adobe Chat.
Hopefully Adobe Chat should be able to take care of the serial number matter even though Premiere Elements 10 is not the current version. If it rejects the request because it feels that the matter is "Tech Service" instead of "Serial Number Issue", then there may be a problem because 10 is not the current version.
If that is the case, we could consider trying the serial number is a tryout of Premiere Elements 10 from
If it comes to this, make sure you read closely the "Note: Very Important Instructions"
Please let us know the outcome.
Add On...are you doing the install with antivirus and firewalls turned off?
Supplemental Information if needed....
Please check out my prior experience with Photoshop Elements 12 Premiere Elements 12 Invalid Serial Number.