Hi Saskiavan,
Thank you for contacting the Microsoft Community.
We appreciate you for reaching out and providing a detailed overview of the steps you've already taken to address the issue with downloading files from the learning download center. I can sense how difficult it must be to encounter this error despite trying various troubleshooting steps.
Your proactive approach in attempting different solutions is commendable, and I value your efforts in trying to resolve the issue independently.
I assure you that we will continue exploring other avenues to address this concern, which is why I will be engaging with our support group for assistance.
Having said this, for us to be able to replicate the issue and for my support team to mitigate the process, please provide us with a step-by-step screenshot using the Problem Steps Recorder (PSR) tool (click this link for MAC devices), starting from the login page until you have reached the page that shows the "Error downloading file" error message.
You can refer to this link as your reference guide.
Kindly attach the PSR file via the private message I have initiated, along with the information to locate and verify your profile. Upon receipt, I will promptly forward the matter to our dedicated resolution team for further investigation.
I look forward to your response. Please note that if no response is received after two business days, the case will be closed and locked. After the case is locked, we will no longer be able to respond, even through Private Messages.