Does anyone know how to fix this?

[Brent33621532zxku]

 I try to upload a character and even though I placed ALL the markers down, this shows up

[Ussnorway · Accepted solution]

unknown error tends to translate as Mixamo can't read the file; it may be too big, have old image formates like TSO or just be a rubbish which doesn't fit a human shape... you didn't include enough info to make a guess