Running Low on memory

@morgan34188729f20k No, 4 GB of RAM is not enough to use Premiere Pro. Our minimum requirement is 8 GB for HD frame sizes and 16 GB or more for higher frame sizes or complex projects.

Your external 2 TB is storage, which is not related to the RAM inside your system (though they are both measure in GB or TB).

Memory (RAM) is the specialized active memory chips your computer uses to hold what it is currently working on. Anything that is open on your computer (web browser, Premiere Pro, other applications, etc) is using RAM. If your system doesn't have enough RAM to hold all the things it is trying to do, you will notice very slow perfromance and/or strange behavior or errors like the one you are describing. For best performance with Premiere Pro you'll either need to install more RAM if that is possible on your system, or, move to a system that has at least 8 GB, ideally 16 GB of RAM.

i only have 4GB on my laptop but have a 2 TB external drive is that sufficient?

@morgan34188729f20k how much physical memory (also known as RAM) is in your system? You can use Task Manager on Windows or Activity Monitor on macOS to see how much Memory is free before you launch Premiere Pro, and then afterwards. We recommend a minimum of 8 GB of RAM, ideally 16 GB, to use Premiere Pro.

https://helpx.adobe.com/premiere-pro/system-requirements.html

Hola, has tratado de restaurar tus preferencias de programa, o borraste el cache de medios.
Estos por lo general suelen dar estos problemas.
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