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Photoshop 2021 version 22.3.1 should work for a period of 7 days installed on a machine where the installing users does not have an Adobe account that has a subscription for Creative Cloud Photoshop, Photoshop will not be activated.  7 days after your first Photoshop test Photoshop should stop working for it not activated and its past the 7 day trial time.  You should be able to Activate the trial installed by obtaining a subscription and use the creative cloud desktop application sign in with your adobe account that has a subscription for Photoshop.   If your Photoshop trial did not function it may be because your machine does not meet requirements or there is an issued in Photoshop 2021 version that causes it to crash, or your install and tried to use Photoshop more than 7 days ago  you trial for Photoshop 2021 version 22.3.1 is over and it was not able to run on your machine.  Look to see it there are any crash reports on your machine for Photoshop.  Currently the are many unresolved issues in Photoshop 2021. Many have issues with Photoshop 2021 on their machine.  Photoshop 2021 runs on most machines but not without issues.  Photoshop 2021 has unresolved issues.  Photoshop may crash if your Display adapter device driver is not the latest its GPU support may need to be updated.