Elements won't show or play back iPhone .mov videos

>or see them but in grey

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

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

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

There are also intermittent reports that the newest driver is not always the best driver due to driver bugs or compatibility issues, so you MAY need to try an earlier driver version

Did you click on Click Here for more information?

Did you install the codec?