‘ExtFS for Windows’ is a free program from ‘PARAGON’ software group that enables Windows users to access their Ext 2/3/4 file systems directly from ‘My Computer’. I have had used this program in its early days not ever since, but recently I came across it quite accidentally and decided to give it a go under Windows 8.
But before I begin, let me give you a brief introduction to this utility because I think it is important. This tool uses another utility called ‘Dokan’ (a separately developed utility, now abandoned). To spare you with the boring technical details, ‘Dokan’ acts as the middle man between Windows’ Kernel and the Paragon’s utility that actually deals with the ‘Ext’ file systems.
In other words, when you access a ‘Ext’ file system under Windows using ‘ExtFS …’, Windows passes your request to ‘Dokan’, and then ‘Dokan’ passes that to the Paragon ‘Ext’ mounter. When the ‘Ext’ mounter done doing its job (say a file read), then it passes that data to ‘Dokan’ and ‘Dokan’ then passes it to Windows. In other words, neither the Paragon’s ‘Ext’ mounter nor Windows operating system are aware of each others existence, which is also why, the mounted ‘Ext’ file systems are displayed as ‘Dokan’ in Windows file explorer, not as ‘Ext 2/3 or 4’.
Now let me come back to the story. I used Ubuntu 13.10 and ‘KaOS 2014‘ (both residing on ‘Ext4’) for testing this tool (version 2.73, Windows 8 64-bit), on two different occasions, and the results were pretty much identical.
First I tried reading a web page, a ‘Zip’ file and a video file. The web page and the ‘Zip’ files were read without any issues, but the video playback was interesting. First I tried playing it through ‘PotPlayer’ and it continuously skipped frames while playing. Then I tried it under VLC and it just gave this big fat error and exit.
Windows Media Player however, played the file perfectly well!.
How is this possible ? I do not know the exact reason, but my guess is, it is because of ‘Dokan’. Although not always necessarily true, if it was the Ext mounter’s fault, then all the media players should have failed because there was very little ‘Dokan’ could do, if Paragon’s Ext mounter provided it with corrupted data reads. But no, the playback was perfect under one player while two others failed.
So why did not the web page and zip file readings fail ? Playing a video (or any multimedia file for that matter) is a bit different than opening a web page or a zip file, because a video player does not request the whole file to be loaded when playing, it only requests its content on demand. This increases the communication instances between ‘Dokan’ and the Ext mounter (in this case), and since ‘Dokan’ does not officially support Windows 8, it could simply be the result of a ‘bad communication’ (again, this is just a guess).
I also tried copying few files into the ‘Home’ folder, although after they were copied I could see and access them in Windows 8 (sometimes only), when I tried rebooting to see if I can read them in Ubuntu (and ‘KaOS’), on more than one occasion, I got the ‘file system corrupted …’ error (shown below is one that I received in Ubuntu).
I was able to fix the issue by running ‘fsck’ (command-line based GNU/Linux file system checker) manually, but that took away the file. On another occasion, after copying a video (about 74.4MB) file I booted into Ubuntu and although I did not receive any ‘file system …’ errors, ‘Nautilus’ showed its size as ‘15.8KB’ and it was not readable.
So who’s fault is it, this time ? I do not know because I am not an expert on file systems, but this time it could have been Paragon ‘Ext’ mounter’s fault.
But the point is, if you are planing on using this utility under Windows 8, I would advice against it, and there is no option to use it with read-only permissions either. That said, I do not know whether it works on other versions of Windows, though from the look of things, it should be dangerous to use under Windows 8.1 as well.