Slow file upload speeds in windows 10 guest

Hi. I’m having a strange issue where in the VM, speedtest performs as expected, however when trying to upload files (pictures to discord, videos to streamable for example) it’s extremely slow to the point of being nearly unusable. Downloading works fine.

The thing is, I already solved this early this year. I recall a thread on social.technet.microsoft.com that had a simple solution to this, something like just changing a setting or ticking a box in windows network settings. However, for the life of me, I cannot find this thread again. Now I’m in a new VM, and facing this problem again.

Hopefully someone who sees this has an idea of what I’m talking about.