wifi router upgrading problem

[profkefah]

i have problem with router tp link wr940 n v 2.0
it has a problem that i can conect to it but without geting internet
so i tried factory reset many time with no result
then i tried upgrading
i dowonloaded firmare frim your support and when i try upgrade i get
invalid file format
also the info in the panel show that the device is not wr940 n v 2.0
but wr940 v5

in the device info
asnd on sticker

plez help me

 

[rgd1101]

It this bought new or used?
The firmware said it is a TL-WR941ND V5
http://www.tp-link.com/en/download/TL-WR941ND_V5.html#Firmware

 

[profkefah]

the router is old

when i tried both firmware
v2 and v5
i get this message
invalid file format

 

[rgd1101]

Did it ever work before? look like a fake

 

[profkefah]

ok
the router is genuine
it worked before perfctly
its owner said
the router stopped working before 2 months and one of his relative fixed it now
but the problem rreturned again
i can coneect to the routewr but no internet

 

[profkefah]

any help plez