I've seen many posts about this but none of them actually has a solution that worked for me.
I have a Sensation XE, I don't know the cause of the problem exactly, but I had it on recovery and it discharged (deep discharge).
Now whenever I try to turn it on, the red led on the left top corner turns on, sometimes the device vibrates, but the screen stays off.
I tried to go into bootloader but with no luck, same for recovery.
The charging orange led does light up when the device is plugged in, and I've checked the battery, it's functional. I even tried another battery just to make sure.
I tried to charge it overnight, and I tried to charge the battery on it's own, with no luck.
One thing I found right before I post this is charging the phone with the battery out!
Now I don't know how that might help as the device doesn't boot with no battery, but I tried it anyways just to make sure I haven't left anything to chance, and it didn't work.
This thread might come in handy for other people with the same situation.
Windows 7 recognizes the device when plugged in as "Android ADB Interface" but when I use "adb devices" it doesn't show anything.
I tried the Sensation Unbricking Project, the terminal always said "Bricked device found on." but it doesn't give me the next line "sdX", I think it doesn't recognize the device.
In the video when the device is plugged in, Ubuntu immediately recognizes it and it even opens up the device's files, that does not happen with my device.
I don't remember exactly my bootloader information, but I think my HBOOT version is 1.27, not sure about that.
I have bootloader unlocked with S-ON, and I had a custom ROM running for over 3 months when all this happened.
I hope you have all the info you need to help me, if not just ask me, any help would be much appreciated.
Thanks in advance.