I cant open my Premiere Elements 2021 and cannot use it. I tried reinstalling but keep getting an errorr message that the keys are wrong. IS there any way I can use this again?

That makes sense, Bill. In which case it sure could be that the program is too old to activate.

I am confused… 1st you say you are asked to register, now you say the program does not open

Are you on Mac or Windows, and exactly which operating system version?

If Windows there are a few things to try

https://learn.microsoft.com/en-us/cpp/windows/latest-supported-vc-redist?view=msvc-170

https://helpx.adobe.com/x-productkb/global/troubleshoot-c-runtime-errors-products.html

Do not count on Windows to be fully up to date when it comes to device drivers
Go to the vendor site to be sure you have an updated driver for your graphic adapter
There have also been reports in the past that the latest driver is not the best driver
.
Also check (copied link) https://www.tomshardware.com/reviews/gpu-hierarchy,4388.html

.
nVidia Driver Downloads https://www.nvidia.com/Download/index.aspx?lang=en-us

-for all Adobe programs use the STUDIO driver, not the GAMING driver
-To achieve the highest level of reliability, Studio Drivers undergo extensive
-testing against multi-app creator workflows and multiple revisions of the top
-creative applications from Adobe to Autodesk and beyond
.
If you have a laptop you MAY also need to check for a laptop specific nVidia driver
-SOME laptops require an approved driver from the laptop company, not nVidia
.
AMD/ATI Driver https://www.amd.com/en/support

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Intel https://downloadcenter.intel.com/product/211969/Intel-HD-Graphics-Family

https://www.askwoody.com/newsletter/free-edition-working-with-the-intel-driver-support-assistant/

I downloaded the application and have been using it. I have thr right serial numbers and the application does not open.

A few years ago Adobe stopped support for all but the current versions of Premiere Elementst and Photoshop Elements. You can still use older versions if they’re already installed on your computer -- but you won’t be able to activate a new install or a reinstall. That’s likely the problem.

Although I’ve never seen an error that says your “keys are wrong.” What does that even mean? Can you post a screen shot of this error message.