mount error 13 = Permission denied

A couple of things to check out. I do something similar and you can test mount it directly using the mount command to make sure you have things setup right.

Permissions on credentials file

Make sure that this file is permissioned right.

$ sudo ls -l /etc/smb_credentials.txt 
-rw-------. 1 root root 54 Mar 24 13:19 /etc/smb_credentials.txt

Verbose mount

You can coax more info out of mount using the -v switch which will often times show you where things are getting tripped up.

$ sudo mount -v -t cifs //server/share /mnt \
    -o credentials=/etc/smb_credentials.txt

Resulting in this output if it works:

mount.cifs kernel mount options: ip=192.168.1.14,unc=\\server\share,credentials=/etc/smb_credentials.txt,ver=1,user=someuser,domain=somedom,pass=********

Check the logs

After running the above mount command take a look inside your dmesg and /var/log/messages or /var/log/syslog files for any error messages that may have been generated when you attempted the mount.

Type of security

You can pass a lot of extra options via the -o .. switch to mount. These options are technology specific, so in your case they're applicable to mount.cifs specifically. Take a look at the mount.cifs man page for more on all the options you can pass.

I would suspect you're missing an option to sec=.... Specifically one of these options:

   sec=
       Security mode. Allowed values are:
       ·   none - attempt to connection as a null user (no name)
       ·   krb5 - Use Kerberos version 5 authentication
       ·   krb5i - Use Kerberos authentication and forcibly enable packet 
           signing
       ·   ntlm - Use NTLM password hashing
       ·   ntlmi - Use NTLM password hashing and force packet signing
       ·   ntlmv2 - Use NTLMv2 password hashing
       ·   ntlmv2i - Use NTLMv2 password hashing and force packet signing
       ·   ntlmssp - Use NTLMv2 password hashing encapsulated in Raw NTLMSSP
           message
       ·   ntlmsspi - Use NTLMv2 password hashing encapsulated in Raw 
           NTLMSSP message, and force packet signing

       The default in mainline kernel versions prior to v3.8 was sec=ntlm. 
       In v3.8, the default was changed to sec=ntlmssp.

You may need to adjust the sec=... option so that it's either sec=ntlm or sec=ntlmssp.

References

• Thread: mount -t cifs results gives mount error(13): Permission denied

Thanks, but some more googling turned up the solution. It was using the wrong security type by default; this command worked:

$ sudo mount -t cifs //172.16.1.5/myshare/ /mnt/myshare \
    -osec=ntlmv2,domain=MYDOMAIN,username=myusername,password=mypassword

I ran into this problem and the issue turned out to be not formatting the values in my credentials file correctly. I tried:

username=DOMAIN\mylogin
password=<password>
domain=FULLY.QUALIFIED.DOMAIN

I also tried:

[email protected]
password=<password>
domain=FULLY.QUALIFIED.DOMAIN

And:

username=FULLY.QUALIFIED.DOMAIN\mylogin
password=<password>
domain=FULLY.QUALIFIED.DOMAIN

Once I just used my login username only:

username=mylogin
password=<password>
domain=FULLY.QUALIFIED.DOMAIN

I was able to get my cifs mount to succeed.