mount error 5 = Input/output error

I am running out of ideas. After a long period of testing this morning, I cannot seem to get this to work, and I have no idea why. I want to mount a Windows SMB/CIFS share with a Debian 5.0.4 VM, and it is not cooperating.

This the command I am using.

debianvm:/home/me# whoami

root

debianvm:/home/me# smbclient --version

Version 3.2.5

debianvm:/home/me# mount -t cifs //hostname.domain.tld/share /mnt/hostname.domain.tld/share --verbose -o user=SUBADDOMAIN.ADDOMAIN.DOMAIN.TLD/username

mount.cifs kernel mount options: unc=//hostname.domain.tld\share,ip=10.212.15.53,domain=SUBADDOMAIN.ADDOMAIN.DOMAIN.TLD,ver=1,rw,user=username,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,pass=*******************mount

error 5 = Input/output error Refer to the mount.cifs(8) manual page (e.g.man mount.cifs)

debianvm:/home/me#

The word on the nets has not been very specific, and unfortunately it is almost always environment-specific. I receive no authentication errors. I have tried mount -t smbfs and mount -t cifs, along with smbmount and such. I get the same error before. I doubt it is a problem with DNS resolution, because logging shows the correct IP address. dmesg | tail -f no longer shows authentication errors when I format the domain and username accordingly. I have played a little with iocharset=utf8, file_mode, and dir_mode as described here. That did not help either. I have also tried ntlm and ntlmv2 assuming it might be a minimum auth method problem, but not forcing sec=ntlmv2 it can still authenticate without errors anymore. smbclient -L hostname.domain.tld -W SUBADDOMAIN.ADDOMAIN.DOMAIN.TLD -U username correctly lists all the shares and shows it as the following.

    Domain=[SUBADDOMAIN] OS=[Windows 5.0] Server=[Windows 2000 LAN Manager]

Sharename       Type      Comment
---------       ----      -------
IPC$            IPC       Remote IPC
ETC$            Disk      Remote Administration
C$              Disk      Remote Administration 
Share           Disk      

Connection to hostname.domain.tld failed (Error NT_STATUS_CONNECTION_REFUSED)
NetBIOS over TCP disabled -- no workgroup available

I find the last line intriguing/alarming. Does anyone have any pointers!? Maybe I misread the effin manual.