Here is the file that I am trying to findout a way to decrypt.
This file is from the settings of the MetaTrader 5. The same is the name of the application.
Kindly suggest a better way so that I could read what is there in the encrypted settings file.
There’s very little chance of success if both encryption algorithm and the key is unknown (besides trivial cases like single byte XOR) so you need to work on discovering those things. Since you have the program which can read the file, the information must be inside it. You can try to find the decryption function by static analysis (disassembly/decompilation) or dynamic (debugging). Once you found it, you can either try to determine the algorithm (e.g. from the magic constants used by the code) or treat it as a black box and reproduce the algorithm in your own implementation. One more approach is to use the code as is and either call it with your own data or run the program normally and capture the data in memory one it’s been decrypted.
In summary, there is no magic one click solution but as long as you have something which can decrypt the file and can inspect/observe it, the task is solvable.