Default After several tries still in bootloop - HTC One X

Hi Community,

I have a massive problem and I hope you can help me.

I rooted my HTC One X successfully and tried to flash custom roms on it which kind of worked. I put the zip folder on the internat sd card and flashed it without flashing the boot.img.
Finnaly I found out to do that, flashed the boot.img but while installing the ROM the problem code/status 7 appeared and I had to restart the phone in order to put the right rom onto the phone, which i had on my computer.
But while booting, the phone just got stuck in bootloop showing the HTC logo.
I already tried quite a lot of stuff to rescue my phone, for example to restore the nandroid backup - didnt work, flash another backup onto phone - still bootloop, flashed a new rom with boot.img - still bootloop.
The only solution i could find was to unroot the device and flash the stock rom onto it.
Is that really my last resort or is there another way?
Thanks for your help.