Identifying File Type of a File without extension

I have a quite a large file (>50gb) that has no file extension and is possibly encrypted. I created this file a while ago, but I accidentally removed the extension but I think it is possibly a compressed file (e.g. .7z, .rar). I know the password if I am able to identify which application can open it.

How is it possible to identify which file type this file belongs to (bearing in mind it might be encrypted - but I know the encrypted password if there is one)?

I tried using a Hex Editor but weird characters are shown most likely because it is encrypted.

Further Information: Hopefully this should be helpful:

I would have created this file on a Windows operating system
The hex editor has text 0x0 to 0x200 followed by a massive whitespace before contents/text resumes at 0x20000.

waqasahmed

Posted 2017-04-20T23:57:27.797

Reputation: 103

A compression utility such as 7zip should be able to identify the file even without an extension. Just try opening it with this app. – music2myear – 2017-04-21T00:09:55.007

Answers

Assuming that by "encrypted" you mean that you used a password during the compression process to encrypt the file, 7Zip can handle this without issue.

If you have the 7zip shell extension, just right-click on the file and select the 7zip option to extract. It'll identify the file itself and present a password prompt to you for decryption.

I tested this just now by creating a 3GB archive from an ISO with a password (and encrypted file names), removed the extension, and asked 7zip to open it.

music2myear

Posted 2017-04-20T23:57:27.797

Reputation: 34 957

Yes by encrypted I mean password protected. 7-zip (Ez7z) gives me the following error: "Can’t make last item of {} into type string. (-1700)". I think on Windows it says not valid archive. – waqasahmed – 2017-04-21T01:06:15.900

1Then it sounds as though you can probably add corrupted to the list of characteristics of this archive. – music2myear – 2017-04-21T03:22:58.250

+1 - You are probably right - Thanks for your help! – waqasahmed – 2017-04-21T11:18:28.297

did you try on *nix ?:
#file your_filename
where "file" - is a program usually lives here /usr/bin/file you can install it using package manager, or get it there ftp://ftp.astron.com/pub/file/

Gena Gordeev

Posted 2017-04-20T23:57:27.797

Reputation: 51

I have tried on mac - it just says filename: data where filename is the name of file. – waqasahmed – 2017-04-21T01:01:36.217