For modern MT4 builds (including anything recent like 40432), fully automated, free decompilers generally do not exist.
While decryption is theoretically possible, it usually requires: ex4 to mq4 decompiler 40432 updated best
If you find a tool claiming to be the "best updated decompiler" for free, it is almost certainly a scam or a virus trap. For modern MT4 builds (including anything recent like
Decompiling EX4 files back to MQ4 source code is: If you find a tool claiming to be
Decompilers bypass the compiled protection that developers pay for when selling their trading systems.
Even if a decompiler manages to generate an MQ4 file from a modern build, the code is rarely perfect.
If you purchased an EA and want to see the code to modify it or verify it isn't a scam: