black stripes in the preview

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 http://www.nvidia.com/Download/index.aspx?lang=en-us
-for Premiere Pro and MAYBE Premiere Elements use the STUDIO driver, not the GAMING driver
-such as (this MAY not be the latest) https://www.nvidia.com/en-us/drivers/results/170344/
If you have a laptop you MAY also need to check for a laptop specific nVidia driver
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

The probable issue is that your video driver was somehow changed.  It may have been part of an operating system change.  The usual solution is find the current video driver and install it.  If you have an Invidia GPU, consider the "Studio" driver instead of the "Gaming"driver.