Decrypt failed, Boot Error topic

after flashing new updated firmware for XTOUCH PF81 tablet (mtk6577) , its stuck at boot with this message : Decrypt failed, Boot Error .
any way to decrypt this firmware or to get authorized security or uboot img files to solve this ??
appreciate your help.
note : the firmware which downloaded are official from XTOUCH page .

decrypt storage topic

everytime i install a new rom or a new cwm it says decrypt storage when i boot up. why

[Q] Decrypt failed, Boot Error topic

hello
after flashing new updated firmware for XTOUCH PF81 tablet (mtk6577) , its stuck at boot with this message : Decrypt failed, Boot Error .
any way to decrypt this firmware or to get authorized security or uboot img files to solve this ??
appreciate your help.
note : the firmware which downloaded are official from XTOUCH page .