Mounting an ext3 file system under Windows can be done in various ways. However, out of all the programs I (AlexRoman) have tested, only one seemed to satisfy all the requirements (stability, speed, ease of use, works on XP SP2, etc.) That program is called EXT2-IFS and it can be found on http://www.fs-driver.org.
This software doesn't work on LVMs. If you're creating the Linux system from scratch, force it to not use LVMs. Otherwise you'll be reinstalling Linux from scratch.
The permissions of files are not maintained. You will have access to all the files of all the users. If you mount your root (/) partition, you will have access to critical system files! Be careful with that!
When creating a new file or directory it will inherit the permissions (user and group) of the parent directory. There is one exception to this. When creating a file, EXT2-IFS will not give it an execute permission even if the parent directory has the execute permission.
Also, files and directories starting with a dot (.) will be treated just like normal files and directories.
Special files are sockets, soft links, block devices, character devices and pipes. EXT2-IFS will not allow access to these file types.
Alternate 8.3 DOS names are not supported. The reason for this is that there is no place to store them in the ext2/3 file system hierarchy. This can prevent legacy DOS applications executed in Windows through NTVDM to operate properly.
Defragmentation and displaying fragmentation information is not supported. Thus you will not be able to use any of these functions on a mounted ext2/3 file system.
Alternate codepage support (including UTF-8) is not supported. The default Windows codepage will be used.
You will not be able to boot a Windows operating system from an ext2/3 file system using this driver.
Linux kernels versions 2.2 and less were not able to write files larger than 4GB on ext2/3 file systems. Enable the large file feature if your Linux distribution has a kernel more recent than 2.2 (2.4 and up). Disable it otherwise.
Before installation, see the Features and the Things to watch out for sections above.
The installation of EXT2-IFS is fairly straight forward. It is a simple Next -> Next -> Finish process. The only thing you want to look out for is the large file feature. See the explanation above.
Using an ext2/3 file system is very straight forward. You can use it just like you would use a normal mounted FAT/FAT32/NTFS file system: through the My Computer / Windows Explorer interface.
-- AlexRoman - 04 Aug 2005