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I had enabled Sd Card Encryption in my "HTC Desire 816 (d) phone in July 2015, after that I had taken backup of "Phone memory" in my computer, But few days back my phone got stolen. Due to which I m not able to view images encrypted in Sd Card. How can I decrypt or view images encrypted in Sd card, in other phone?

Kindly help me.

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Answer: You cannot decrypt, since it requires both the device and the key which was generated on it to encrypt

Why

Encrypt Files on Your SD Card Using Your Android Phone explains this in simple terms. Quoting relevant portions (emphasis added; deleted text denoted by "...."):

Unfortunately, it is virtually impossible to access or decrypt the files on your SD card without the right password. Android's encryption algorithm is based on two major factors - the mobile device and the password. Lose any of these, and your encrypted SD card files will be inaccessible. You can only decrypt the SD card files by inserting the SD card into the mobile device that was used to encrypt it and then entering the correct password when the device is powered on.... The password or key is stored to your mobile device's Random Access Memory (RAM)....Encryption is essentially classified as a high level data storage security process. When you encrypt a file, you are altering its form using a specific algorithm so that the operating system will not be able to readily classify or identify it. With advancements in information security, the encryption algorithms being employed nowadays are basically "fool-proof". This means that there is no viable way of opening an encrypted file other than getting a hold of the key. Even hundreds of supercomputers could take thousands of years to open an encrypted file.

Encryption is designed to work this way for one obvious reason: Security

To further clarify on the query of OP- again, No, you require the same device on which it was encrypted, it will not work on same model device. A simple explanation for this is

The password or key is stored to your mobile device's Random Access Memory (RAM) ( hence, you require the same device)

The underlying principle is that data and key required to access it should be in separate physical/logical locations. While the algorithm for key generation is OEM specific, the actual key generated is linked to the device on which it is generated and hence decryption will not work if the device is changed, since the "key" portion of the puzzle is missing

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    Can you mention why the same mobile device is required? The quote you used doesn't shed any light on deep technical aspect of the issue. I'm not asking for some cryptic names but a bit more technical context on why that same device is required would do good for curiosity. You can find and add related (do read them of course) readings if you find any difficulty expanding the answer beyond a certain technical point.
    – Firelord ♦
    Commented Jan 19, 2016 at 9:42
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    To be honest, as a security enthusiast, this answer is pretty good as in means of explaining the basic lines. However as Firelord points out, misses some certain points. Still upvoted. 9/10 would upvote again.
    – SarpSTA
    Commented Jan 19, 2016 at 9:44

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