Here is some information regarding the E04 error message from
http://www.techlore.com/article/10974/JVC-Camcorder-Stuck-in-Safe-Mode/:
"JVC notes that you are also given a malfunction code when the unit is placed into safeguard. If it displays code 01, 02, or 06 you should remove
the battery and powersupply and wait for a while. Code 03 and 04 indicate that you should eject and reinsert the tape.
If neither of these solutions work, your only alternative is to bring it to a shop or send it to JVC for diagnosis or repair. Unfortunately, there is no other way to clear the condition."
This doesn't seem uncommon, and indicates a bad tape is loaded, or unfortunately, that the camcorder requires servicing.