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Did you make sure you had a good connection on the jumper cable ends on the donor car? What gauge jumper cable wires are using? Do you have a push start system or mechanical key system? When you turn the key to the start position is there a rapid clicking noise and the dash lights dim and flash in unison with the clicking noise? Did you try starting in the neutral?
The problem is not the battery or the jumper cables at this point if the security system keeps going off its overriding the starter circuit. Toyota security systems do no do this. This is some type of aftermarket security system. You're not going to get it to start unless you can get a remote to shut the system off in some cases if you have the key in the on position and you disconnect the negative battery cable for about 10 minutes and leave the key in the on position reconnect the cable sometimes it'll override these aftermarket security systems. Worst-case scenario you have to have it taken some place where they can remove the system is probably faulty.