Hi Benjamin, Thanks for responding. The credentials file is a simple text file created with vi containing the lines: >> username=<user> password=<password> << I have tried this both with and without trailing newline at the end of the second line. I have also tried the variant: >> username=<user> password=<password> domain=<domain> << The results are always the same. If there is a problem with the *content* of the file, why would the error message say that the file could not be opened? Thanks for your help! Best Regards, Roger From: Benjamin Bellec [mailto:b.bellec@xxxxxxxxx] Sent: Saturday, November 1, 2014 1:34 PM To: Roger Brooks Cc: linux-cifs@xxxxxxxxxxxxxxx Subject: Re: Unable to mount using credentials file Hi, Does your credential file is correctly formatted ? 2014-11-01 13:03 GMT+01:00 Roger Brooks <r.s.brooks@xxxxxxxx>: I am attempting to mount Windows volumes on a Synology DS (running DSM 5.0, a Debian-based distribution). Command lines of the form: mount -t cifs -o username=<user>,password=<pass> //<IP address>/share/ /mnt/<mountpoint> succeed. However, command lines of the form: mount -t cifs -o credentials=<filename> //<IP address>/share/ /mnt/<mountpoint> fail with the error "Invalid argument". For diagnostic purposes, I have attempted to mount the volumes directly using mount.cifs (v5.5). Once again, commands of the form: mount.cifs //<IP address>/<share> /mnt/<mountpoint>/ -o username=<user>,password=<password> succeed. However, commands of the form: mount.cifs //<IP address>/<share> /mnt/<mountpoint>/ -o credentials=<file> fail with the error message: error -1 (Unknown error 4294967295) opening credential file <file> This is the case regardless of the location of the file (see http://samba.2283325.n4.nabble.com/Error-s-opening-credentials-file-td2518214.html) or its privileges. The error persists, even when the command is executed from a root session and the credentials file has permissions 0777 and is in a subdirectory of /root. How can I get mount to work using a credentials file? -- To unsubscribe from this list: send the line "unsubscribe linux-cifs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-cifs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html