Recently we had a Mac not be able to access a Windows Samba (SMB) Share

Thinking a windows update could have caused some issue, we tested another Mac but it worked fine 

OS X Mavericks 10.9 brings a change of SMB2 instead of SMB1 , which can be disabled with the below command 

echo "[default]" >> ~/Library/Preferences/nsmb.conf; echo "smb_neg=smb1_only" >> ~/Library/Preferences/nsmb.conf

This still didn’t work so we reverted back to SMB2 with the below

rm ~/Library/Preferences/nsmb.conf

I used Telnet to make sure there wasn’t a network issue on port 445 ( Open Terminal , enter Telnet and open IP 445) which worked

I installed a trial of this on the Windows File Server which creates an AFP share , which worked by is 1000$!

https://www.acronis.com/en-au/mobility/mac-windows-compatibility/

We upgraded the Mac to the latest OS 10.14 ( for free )  and it solved the issues