Strange FTP issue (Server 2003)
Posted on 2013-10-09
We have a strange problem with FTP access to one of the sites on Web Server 2003.
Hoping someone can help.
We have a Server 2003 that runs IIS and has about 40-50 sites with FTP access.
No one seems to have this problem except for one website. Granted the site is rather poorly looked after with some filenames containing spaces etc. and with the total folder size of 330MB. Most images on the site are disproportionately large and what have you.
In its current state when I attempt to establish a remote FTP connection to the site, it just throws up error: "An error occurred opening that folder on the FTP server. Make sure you have permission to access that folder. Details: The operation timed out" and refuses to load anything.
We have a firewall enabled for the network connection over which FTP requests are transmitted with the exceptions for various FTP services and a range of passive ports: 10001-10100.
When the firewall is enabled for this network connection, the FTP connection to this problematic site is attempted via 5000 range port (i.e. 5003, 5005 etc.) and when I switch the firewall off and retry the connection, it then connects and loads the FTP contents successfully but via 10000 range ports (i.e. 10002, 10006 etc.)
In short when firewall is off it uses 10000 range ports and is successful, when firewall is on it tries to use 5000 range ports instead and fails. Other sites that are hosted on the same server are not affected by this change and are always successful when FTP connection is attempted no matter if Firewall is on or off.
I've tried adding a couple of 5000 range ports (5000-5005 to be precise) to the exception list to see whether that makes any difference but it didn't.
Other weird thing that baffles me is when I take out (delete) one folder from the root of the site which contains web images then I'm able to establish a successful FTP connection to that site even though the firewall is still on. Image folder size in question is 95MB.
What's even weirder is that when I re-create a new BLANK folder in the root of the site and call it "images" (same as the original folder was called) and leave it blank and then retry the FTP connection then it fails immediately again.
The site is written in plain HTML and is rather old and messy (not our fault promise) but we never had problems with it before just recently it suddenly started doing that. I'm not aware of any recent changes in configuration either.
Tried in windows explorer and other FTP clients such as: Filezilla and FireFTP
Plain mystery to me.
Thanks in advance for any tips and help.