I know there are many commercial products that accomplish this task, but I'm looking for something like SSHFS but for Windows systems, which is open source.
The standard choice is ExpanDrive (formerly SftpDrive), which is neither OSS, nor free ($39 for full version).
I haven't yet found mature OSS alternative.
If anyone is interested, we offer free SFTP Net Drive application for exactly this purpose. It's not open-source (as it uses commercial components), but completely free.
Update: source code of SFTP Net Drive is included as one of sample projects with our Callback File System product.
I had this question today as well, and came across this good article, telling about 2 programs mentioned, SftpDrive and Webdrive:
Best solution nowadays is to use free tool SFTP Net Drive provided by Eldos. We are successfully using it within our supercomputing clusters and it work fine. We wanted to get rid of Samba.
A reboot is officially required after installing, but Win-SSHFS worked without rebooting. Beware of data loss on writes - see this Google Code issue.
As a perhaps overly complicated solution, if you have a Linux box on the local network (or a Linux VM running on the machine you want to connect to the SFTP resource with) you could try mount the resource using SSHFS on that machine and share the resulting filesystem to the Windows box via Samba...
I got here from another recent question.
Take a look at freeSSHd (it also supports FTP and, of course lets you SCP too).
Unfortunately it is not open-source. However, its quite good.
Try RedDrive. It's not actively developed anymore (since '08), but it's (apparently) free.
The only freeware tool I found that can map files accessed via SFTP to a Windows drive is Red Drive.
It's no longer developed, and the "replacement", AnyClient, doesn't do drive mapping. There is also a bogus error when you create a connection -
Recovery policy configured for this system contains invalid recovery certificate. Other than that, it worked with one SFTP server and failed authenticating me to another one.
Found a valid installer download link for RedDrive:
In Win7 x64, I had to run the MSI in "Older Windows Compatibility" mode to get it to install (it is not an EXE so you can not pick an OS or Run as Admin).
Hope this helps!
Not an open source, but a free tool, so you may want to check it out.
Works perfectly for plain FTP. I have not used it for SFTP but on the homepage the developer claims "Both unsecured and secured by SSL/TLS FTP connections supported".