frozen on Google logo, error mounting system!

[farisallil]

My phone (GT-I9020T) was not rooted or unlocked and was running on stock 2.3.4
after some app updates, it got frozen on Google logo
I flashed a stock rom using odin and the process was successfully completed but it didn't work

I wiped all data and cache many times.

I unlocked the bootloader and flashed CWM 3.0.2.4

When trying to flash a rom from CWM (without rooting), it stops and says "E: couldn't open rom.zip (bad) installation aborted."

When I try to mount /system, it says "error mounting /system!"
and that happens to data as well

I don't wish to root the phone so it won't be easily brickable as I'm not an expert in this, but I'll try to root it if you guys say that I have to

Please help

 

[suksit]

Try to re-download the ROM package (I'd suggest the OTA for your model.) It looks like the package was not downloaded properly.

Flashing a ROM doesn't require root anyway.

 

[farisallil]

Try to re-download the ROM package (I'd suggest the OTA for your model.) It looks like the package was not downloaded properly.

Flashing a ROM doesn't require root anyway.

I tried that. Didn't work either

 

[farisallil]

any help guys?
at least, how can I format my sdcard before sending it to maintenance? when trying to format through CWM, it says it is formatted but it is not
even mounting it and formatting it through my computer didn't work