A file extension is an optional alphanumeric identifier which comes after the last found period in a file name. A file extension itself does not define what type of data is in a file, but it does give a hint as to what is *supposed* to be in the file.

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Windows 8.1 won't start a file extension using a .jar file, eventhough it's possible in windows 7

Here is a picture of the file i want to open, and the program i want to open it with. If i just click the jar file, it opens my program smoothly (I made that java progrma my self), no questions ...
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1answer
27 views

How to Edit an non-extension Picture?

I have an open source application that i can edit any files on it. Now i want to edit some pictures that have no Extension! (Just the picture name can shown). and when i open them with any ...
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0answers
19 views

LibreOffice: How to open embedded document

I'm using both LibreOffice and MS Office 2010 on Windows 7 with .pptx extension associated with LibreOffice and .xlsx extension associated with MS Excel(I installed MS Office first, and then installed ...
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8answers
138k views

How do you remove a default program association for file types in Windows 7?

I somehow have set the default file type association for a file type in Windows 7. It doesn't appear to be possible to delete it from the "Change the file type associated with a file extension" ...
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2answers
248 views

How to get a text list of files names in a folder in windows

I have a folder that has different file formats, is there a way to get all the files names and their extensions at once instead of copying and pasting
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2answers
37 views

Does changing or removing file extension trick antivirus software?

I have little experience of antivirus software. I wish someone help me with common antivirus behaviors. For example, I have an EXE or PDF file containing virus. Does removing the .exe/.pdf or ...
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votes
3answers
38 views

Windows 7 does not update the default application path

I am developing an application in W7. My application is the default app for TIF files. That means our users can set the app as the default application to open the .tif extension. The problem is, ...
2
votes
1answer
48 views

Windows - don't hide file extensions of certain types

I want to hide all file extensions except for certain extensions/types. Is this possible? I don't like the clutter of file extensions but as a developer I find it helpful to know the extensions of ...
72
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4answers
27k views

Is there a tool that can determine the file type from containing data? [closed]

I sometimes get files from my clients that have the wrong file extension. For example, the name is image.jpg but the file is actually a TIFF image. In many cases I can clarify it by opening the file ...
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4answers
1k views

What does X denotes in ASPX, DOCX, XLSX, PPTX etc?

Previously there were ASP, DOC, XLS, PPT etc and now ASPX, DOCX, XLSX, PPTX respectively. What does X denotes in ASPX, DOCX, XLSX, PPTX etc?
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3answers
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Firefox saves the file without extension

When I download a file, Firefox removes the file extension. I mean, if I download "something.pdf", it saves the file as "something". I didn't have this problem before yesterday. Any help would be ...
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3answers
55 views

Windows wildcards with files having more than 3 characters extensions

On Windows 7, I have a directory containing the following four files: xxx.txt xxx.txt2 xxx2.txt xxx2.txt2 With the file have more than 3 character as a file extension, the behavior of the wildcard ...
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54 views

How to split multiple videos from a single VOB file?

A VOB (Video Object) file is a DVD media extension which can hold multiple videos. How can I split these videos from a single VOB file to multiple MP4 (or other extensions) files on Windows platform? ...
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votes
1answer
31 views

How do I specify that a file extension needs to be run with a switch?

I would like to make certain open with a specific program, but that program requires a specific switch to be provided for it to actually open it. How would I go about setting this up? The specific ...
2
votes
3answers
2k views

changing the nature of .dat file

Some time ago I changed the way my computer reads .dat files by forcing it to always open with KM player. Now, if I save a .dat file in my laptop, its properties says that its a KMP-MPEG file. I want ...
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votes
1answer
2k views

How to set a default file extension for a specific download?

I'm using chrome web browser and when I download a file it saves the file with .jsp extension. Everytime I have to change the extension to my desired extension (i.e. .ica). Just setting the default ...
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3answers
110 views

how to change extension of a file in Windows?

I downloaded a perl file from some webpage by opening it in my browser and saving it. But the saved file has a file name xxx.pl.txt. How can I save it into a file with "pl" as its extension? Also ...
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1answer
167 views

Default file extension for picture downloads on Chrome?

My google chrome will only save pictures as KanKan (then there's some Chinese: 图秀 or something) How do I get it back to .jpeg as a default? (the drop-down menu only says "all files")
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1answer
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Is it possible to change MS paint's default save file type to PNG [duplicate]

Possible Duplicates: How to set default file format for MS Paint How do I make Windows pbrush default to a save-as JPG format? PNG is better than BMP in my work and I too often forgot to ...
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2answers
19 views

What file extensions should be used on GPG generated output?

In Linux file name extensions are irrelevant, but on a Windows system, many GPG users use GUI applications rather than the command line. They may want to be able to double click on an encrypted file, ...
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2answers
46 views

Is there a disadvantage to not using text file extensions?

I recently learned that file extensions (at least for plain text) in a Unix-like environment generally don't have meaning. Whether a bash script has a .sh,.log,.txt, or .hgfjgfdjgd, it can still run ...
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0answers
502 views

How to open a .HM file in Windows7?

I've been sent a document as a .HM file, this is most likely an "Unknown Apple II File" rather than "Windows Help Context IDs" (used by MAKEHM.EXE.) Are there any other applications that save ...
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3k views

How to extract a complete list of extension types within a directory?

Within a directory, and recursively within it's sub-directories, meaning every directory within a directory is processed, how do I compile a complete list of unique extensions within the directory? ...
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2answers
387 views

What are the alternatives of .txt?

For some reason, I can't save .txt files on my web server. I have a text file hosted on my web server, but the ending is not .txt I was wondering what ending should I choose, so that whoever sees ...
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2answers
4k views

Automatically hide files with certain extension in Windows

Is it possible for Windows to automatically hide files with a certain extension? Let's say some program generates a set of files (I cant alter the sources of the program), and I would like some of ...
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4answers
1k views

What are the most popular file extensions for COMPRESSed files? [closed]

I was just wondering, what's the difference between these file formats? Shouldn't there be just one or two that generally tend to perform superior to most others?
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1answer
417 views

Notepad++ find in files filter for files with no extension

I'm using Notepad++'s "Find in Files" functionality to find specific text in a large number of text files across a large number of directories and subdirectories. I understand how to specify file ...
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27 views

More complex file extension on windows using two extension approach?

On Windows, I can have an app associated with *.txt file. So all *.txt open in AkelPad (notepad replacement). However, this editor is great but does not support international characters well. ...
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1answer
42 views

Why is the dot/period character used as file extension separator?

Why dot and not any other character? What's the historical reason behind it?
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1answer
82 views

Figuring out a File's File Extension after it's Changed [duplicate]

Possible Duplicate: How do I find out the file type without an extension? I am wondering if there is any way for understanding for example a file is a video file after we change it's file ...
2
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2answers
147 views

How to add extensions to a lot of files using content of each file?

I've got over 10,000 files that don't have extensions from older versions of the Mac OS. They're extremely nested in file structure, and they also have all sorts of strange formatting and characters. ...
0
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2answers
74 views

How to restore the ability to modify the association for the .txt file extension in Windows 7 Pro?

The Problem: The Properties dialogue box for text files has lost its accustomed Change button From the list of extensions in Control Panel\Programs\Default Programs\Set Associations, the .txt file ...
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28 views

I associated Notepad to .Java files accidently, how do I undo this? [duplicate]

I am using Windows 8, I associated Notepad to open .Java files, all java files changed icon to the notepad one as a default program. I need to undo this step and make java files not associated to any ...
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105 views

Identify recovered filetype

I'm searching some info about this file. It was recovered from a failed HD, with Ontrack EasyRecovery. The file extension may not be accurate. I tried with TrID (I'm the developer), and based on the ...
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1answer
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How to automatically recover lost file extensions?

We're recoverying bunches of data from a crashed partition of which we had no backup, using a data recovery software. Files are getting recovered, but file names are lost. Is there any software or ...
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0answers
23 views

kdevelop: Treat file extension like *.icc as ordinary C++ source file

I have some interface files which are called *.icc. How do I persuade kdevelop (4.3.1) to just treat these as ordinary (C++) source files? When I try to open such a file, kdevelop complains ...
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0answers
51 views

Extracting and viewing the contents of an old game demo's art assets. ART format?

I'm trying to extract some old game artwork from a demo. The demo was for a cancelled game from 1999/2000 based on the tabletop wargame Gorkamorka. The demo can be found here. I've been able to get it ...
5
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2answers
665 views

How does a file have no extension?

Take for instance: cat /etc/passwd Why doesn't this file have an extension such as *.txt*, *.dat*, etc? Or does an extension exist, but it's just being hidden? Does this apply strictly to ...
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2answers
130 views

How can I open a file with Notepad without permanently associating its extension with Notepad?

I’m a developer; I basically work in a Windows 8 environment with several virtual machines running Linux, Windows, etc. I want to prevent Windows associating new file extensions. That is, if I want ...
5
votes
1answer
1k views

How to open file with default program from command line?

If I click on a file in a GUI file explorer, a default program is used to open it. This is useful for files which I don't know how to open from the command line. Is there a way to open a file with ...
0
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1answer
62 views

Incorrect File association for .exe files in Windows

I accidentally chose 'open with this program this kind of file' for .exe files. Now, all the files with a .exe extension open with a particular program. My computer does not have an earlier restore ...
6
votes
4answers
385 views

Are you allowed to come up with any desired file extension (for Unix, Linux, Windows)?

I want to create a file called "message" that contains text only. How does the system know what program to use to read it if I decide to call it: message.txt? message.dat? message.enc? message.cpz? ...
2
votes
1answer
52 views

What is the file name + extension for a file with a period as the first character (example: .txt)?

I'm trying to find an authoritative answer on this matter, but it's difficult. Wikipedia kind of dances around the issue but isn't explicit enough. For .txt (to use an example), is the base name ...
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4answers
32k views

How do I find out the file type without an extension? [duplicate]

After recovering my HDD, I ended up with a lot of files with no extension. Many of them are .bin files. Is there any way to find out what file format they actually are? Many of them have no ...
0
votes
0answers
88 views

How do I open the file with extension .srdt?

Can someone help me out with this. I urgently needed to access a set of files with extension .srdt. I have already tried TrID and it shows the file to be of (zip) type. However I do not know which ...
8
votes
3answers
2k views

On Windows, what filename extensions denote an executable?

On Windows, *.exe, *.bat, *.cmd, and *.com all represent programs or shell scripts that can be run, simply by double-clicking them. Are there any other filename extensions that indicate a file is ...
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votes
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“file.myext” is not a valid Win32 application

I have written a registry that creates .myext. Double-clicking on my file.myext refers to my executable file (converted from a batch file that opens a .jar) which then opens my notepad application. ...
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3answers
464 views

Sending *.exe by changing extension failed

I know you can send .exe through email by changing their extension. I've been using this often. But strange thing happen when I tried to send this specific ".exe" file. It failed!! It's this ...
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1answer
254 views

How to run a file as executable with a different extension?

After taking a look at the listed processes in Window's TaskManager, I've noticed that there are some process that has a different extension other than .exe. I then opened the folder location of one ...
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Multiple extension association

Is there a way to associate an exe to an extension, and another exe when multiple files of the same extension are selected? (e.g.: one mp3 player for a single file, another for a list of files)