djvu can be opened with a program developed by djvu it can be downloaded from their website.
http://www.djvu.org/resources/
In order to open a DJVU file, you will need to double click on the files icon. From there, your computer will locate a program that can open this type of file.
Given the fact that mmg file extension is not common, one needs a specific software to do the same. The mmg file extension allows modifications on Matroska video files.
the extension of a CorelDraw file is .cdr You may open/read/export/recover .cdr files due to software below working with CorelDraw 10, 11, 12, X3, X4 and X5 formats files
You can open these files with Babylon electronic dictionaries software. See www.babylon.com. Microsoft Flight Simulator also writes saved games to the files with such extensions.
There is list of programs that support DO file extension http://www.howopen.org/en/extensions/web-files/do
Adobe Acrobat is used to create and edit PDF's.The file extention need to be .PDF .The files like .docx or doc can be imported in the software and then can be converted to a PDF.So possibly you can open the doc files too in the software.
LBL file extension are for Nicelabel template files. Macromedia Dreamweaver and Sage ACT can be used to open lbl file extensions.
On a handheld with Pocket Excel
The CWK extension dates back to Apple's old Claris Works software. This was later replaces by Apple Works which also used the CWK extension but that has now been discontinued. Apples current iWorks software will open word processing and spreadsheet files with the CWK extension. Failing that try DocXConverter (See links below) and convert the file to another format.
Firstly. .Cr files are uncommon. When found and before you attempt to open them scan then with a good antivirus. Usually .Cr files are associated with CRiSP source code and iris printer ct format bitmap files, crack file and file view pro. In most cases windows intelligence software will attempt to open the file. However if its not resident in the registry then you will have to seek out a software that can open the file in formats you will understand. However, be advised opening any file type you are not sure about can be high risk.
VCD format is already an MPG. It is only masked. Open the VCD in your computer and look for the DAT files (.dat extension), all you have to do is change the extension from .dat to .mpg, that's it, play them.
This is going to depend on the type of file that you are trying to open. The file extension is created depending on the software (and version) that was used. For example, if you use an older version of Microsoft Word to save a document, it has a .doc extension. If you use a newer version such as 2007, it will save the files with a .docx extension. You would need to have the correct software to open the file, but in many cases, Microsoft may make a viewer that you can download (depending on the file of course)