You can’t connect to the file share because it’s not secure
The SMBv1 protocol is a very obsolete protocol. It has been notorious since it permitted many ransomware into the system. After the Wannacry ransomware attack, users were encouraged to disable the SMBv1 protocol from their system. When a series of such attacks repeated, Microsoft finally disabled the SMBv1 protocol in all systems by default.
This Share Requires the Obsolete SMB1 Protocol
Thus, if you are running a system on Windows 10 v1709 or later or you have disabled SMBv1, you will encounter this error. As obvious, the resolution to this problem is to enable the SMBv1 protocol. However, you need to understand the risk involved with it. A wise suggestion would be to enable the protocol temporarily and disable it once your job is done.
The procedure to enable the SMBv1 protocol as follows: 1] Press Win+R to open the Run window and type control panel. Hit Enter to open the Control Panel. 2] Click on Programs.
3] Select Turn Windows features ON or OFF under the green Programs and Features menu.
4] Scroll down the list (which is in alphabetical order) till SMB 1.0/CIFS File Sharing Support option. Click on the + sign next to it to expand the list. 5] Check the box associated with SMB 1.0/CIFS Client.
6] Hit OK to save the settings and restart your system. Now try to map the network share and you would be able to do it successfully. Once the job is done, you should disable the SMBv1 protocol for safety.