Share point mapped drive getting disconnected frequently

Any best practice we need to follow for mapping of share point location ? I am getting errors like

Error Message: A device attached to the system is not functioning
Source: mscorlib
OR

Access Denied. Before opening files in this location, you must first add the web site to your trusted sites list, browse to the web site, and select the option to login automatically

I made sure to add the all share point related url to trusted sites but still getting error.

Any solution please. (Note : I am not allowed to use non official packages)

Thanks in advance.