It took me months to finally figure this out.
I was trying to download videos from Youtube but for some reason the download won't be initiated. I suspected to be some shared folder permission issue. However, I found that was caused by language incompatibility as folder names and file names would be invalid other than English.
Here is what I did.
I created two folders with a English and a Chinese under the same path, granted the same permission. The I tried to download youtube videos with different file names in both languages. All three links have been previously tested working. You can see both the folder and the file have to be in English in order to initiate the download.
My question is, is this an expected issue and assumed to be avoided by user or is it a bug?