@xman Apologies if obvious but did you unzip the downloaded file before uploading via your router's web interface?

xman wrote

Hi,

for some reason I can`t update my vr400 router to latest version, if I download firmware to my pc and than try to upload to router I have error "ERROR CODE: 4503 - The uploaded file was not accepted" and I try few sources and few versions, one example is: https://www.tp-link.com/uk/support/download/archer-vr400/#Firmware

 

When I try to check for new firmware directly from router message was: your firmware is up to date

 

Why? Why I can`t upgrade it to latest firmware?

 

Thanks.

@sc597 Yes, I do that and I do that many times with few firmware versions and also with firmware from few tp-link websites and always I have same error!