Problems connecting to SMB servers; especially through third-party wireless routers (errors -36, -50)

We've received several reports from readers indicating problems connecting to SMB (Samba) servers through certain third-party wireless routers. Users experiencing this issue generally received the error "-36" and a message stating:

"The Finder cannot complete the operation because some of the data in smb://[..] could not be read or written"

We've covered the -36 error message in conjunction with SMB servers a number of times in the past, but never implicating third-party wireless routers specifically.

In Knowledge Base article #301580, Apple says that this error can sometimes occur with SMB/CIFS server that only supports plain text passwords, and offers Terminal-based instructions for enabling Macs to use plain text passwords. Unfortunately, this workaround has not proven successful for some users experiencing this issue.

Other potential workarounds for this issue include:

Modify smb.conf file Open the file /usr/local/samba/lib/smb.conf in a text editor, or type sudo vi /etc/smb.conf in the Terminal (located in Applications/Utilities) open the file in the built-in vi text editor.

Find the line encrypt passwords = yes. This line determines whether or not your Mac will encrypt passwords before sending them. Depending on the configuration of the SMB server to which you are connecting, this line either needs to be commented (disabled) or uncommented (enabled). You can make it commented by putting a semi-colon (;) in front of it, or make it uncommented by removing the semi-colon.

You can also manipulate SMB settings through a GUI with the freeware utility SharePoints.

Re-establishing keychain passwords Deleting then re-entering passwords associated with specific servers can resolve some SMB networking issues. A good way to test whether or not this workaround will bear fruit is to create a new user account (as described in this tutorial) and check for access to the problematic SMB server. If it works, your keychain passwords may be to blame. Go back to the original account, and launch Keychain Access (located in Applications/Utilities). Look for any items that might be related to your SMB server. Delete, then re-establish them.

Try using "Connect to Server" instead of browsing Select the "Go" menu in the Finder and scroll down to the "Connect to Server" option (also accessible through the keyboard combination Command-K) then type SMB://[server name], rather than attempting to browse for servers in the Finder.

Enable CIFS on the server Ask your system administrator to enable CIFS on the server, and attempt to connect via that protocol instead of SMB.

Enable AFP server Ask your system administrator to enable AFP (Apple filesharing protocol) on the server, and attempt to connect via that protocol instead of SMB. AFP is generally faster when accepting access from Macs in any case.

Upgrade to Mac OS X 10.4.x (Tiger) For some users, Mac OS X 10.4.x is able to connect to the same SMB shares that Mac OS X 10.3.x is not.

Upgrade server to Windows 2003 Some users have experienced SMB connection issues when connecting to SMB-enabled Windows 200 servers, but not when connecting to Windows 2003 servers.

Don't block UDP port traffic If you have a Firewall enabled, use the following process to un-block UDP port traffic:

• Open System Preferences
• Select the "Sharing" pane
• Select the "Firewall" tab
• Click the "Advanced..." button
• Turn off the option to the "Block UDP traffic"

Feedback? Late-breakers@macfixit.com.

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