Ubuntu 17.10 mounting smb share keeps failing

I have searched the internet for about 2 hours now but all the suggested fixes do not work. Hopefully someone here knows a good way to fix this issue or can point me in the right direction.

The SMB server is a Synology NAS.

I used this method since Ubuntu 12, but now it will not work. I did the following

1. install cifs

2. edit the /etc/fstab and added the next line

   //servername/sharename /media/<username>/windowsshare cifs credentials=/home/ubuntuusername/.smbcredentials,iocharset=utf8,sec=ntlm 0 0 
   

The troubleshooting i already did

1. Make sure the mount path exists and is empty (/media//windowsshare)
2. Tried all the sec= options available
3. set the rights on .smbcredentials file from 600 to 777
4. Added servername to hosts file just in case
5. Tried adding correct username= and password= instead of the file
6. Tried using the command line instead of fstab

When connecting to the share using the same credentials in the File Explorer (Other Locations -> Connect to Server) it works without any problems.

P.S. This is a clean install of Ubuntu 17.10

The error sudo mount -a displays is:

mount error(95): Operation not supported Refer to the mount.cifs(8) manual page (e.g. man mount.cifs)

If I need to supply any more information please let me know.

Thanks in advance. Chris

Ubuntu 17.10 might have changed the default SMB protocol version used. Man pages says default one is 1.0:

man mount.cifs

I've been able to successfully fix this issue explicitly specifying SMB protocol version 1.0 (vers=1.0) in /etc/fstab:

//servername/sharename /media/<username>/windowsshare cifs credentials=/home/ubuntuusername/.smbcredentials,iocharset=utf8,sec=ntlm,vers=1.0 0 0