Error: Invalid firmware image

I’m attempting to upgrade my Peplink Balance 20 rev 1 from 6.30 build 3100 to 6.31 build 3138 using file fw-b20_30-6.3.1-build3138.

During upload, I get the error:

Error: Invalid firmware image

Thanks.

You have the correct build, so if you are attempting a manual firmware upgrade you could try downloading the image from our web site again to see if that works.