I had to do this a few times. I do nit know why. Just tried adding. Flashed CM mod recovery. Said "successfully flashed ...." Tried booting into recovery. No can do. Pulled battery. Rebooted. Flashed SPRecovery. Hit "reboot into recovery"...Rebooted into SPRecovery mode. Just hit "reboot now"... Once rebooted, went to ROM manager, flashed CW recovery, and hit reboot. Opened into CW recovery mode....
Don't know why this happens, but it is a known issue. I find that I can download ROM's from pc and it works beautifully. I have been using CM since I rooted, as it was only ROM that let my blinking light work while screen was on. I think MIUI does this as well.
If you need help, I can try!
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