restore_net_use

Restores Windows net drives on system boot.

The problem

The problem with Windows 7 and above is that named network connections, e.g., S: are not automatically restored when booting up - the drive icon remain crossed out and the drive inaccessible.

Instead the user must manually fire up Windows Explorer and click on the drive to restore the connection. For the most part this is sufficient, but when using a PC for some automated tasks, it means that after a reboot some manual action can be performed.

The solution

This Python script is intended to solve the problem. It runs the NET USE command, parses the output and tries to restore each connection.

It can optionally log progress to a log file and send mail. If the network interface is slow to come up, the script can first check network connectivity by attempting to contact an arbitrary server (the Google's public DNS server by default).

Usage

The script requires Python (tested with 2.7.15). Alternatively you can package it with, e.g., PyInstaller and run it as a standalone executable. The pre-packaged files are available in the dist subdirectory.

You can read the help by passing argument -h:

quark % restore_net_use.py -h
usage: restore_net_use.py [-h] [--timeout TIMEOUT] [--conntest ADDR:PORT]
                          [--conntimeout CONNTIMEOUT] [--logfile LOGFILE]
                          [--smtp SMTP] [--sender SENDER]
                          [--recipients RECIPIENTS [RECIPIENTS ...]]
                          [--testmail] [--onebyone]

Tries to restore net drives at startup. Calls Windows command 'NET USE' and
parses the connections remembered by the system. It the tries to restore each
connection. Can optionally send mail and write to log file.

optional arguments:
  -h, --help            show this help message and exit
  --timeout TIMEOUT     Timeout in seconds for each NET USE operation
                        (default: 60)
  --conntest ADDR:PORT  Try connecting to ADDR:PORT as a test of general
                        connectivity. The default is Google's public DNS
                        server. Port 445 is SMB port (default: 8.8.8.8:53)
  --conntimeout CONNTIMEOUT
                        Timeout for connectivity test. Do not test if
                        undefined (default: None)
  --logfile LOGFILE     Write messages to this log file. Do not write if
                        undefined (default: None)
  --smtp SMTP           SMTP server for sending messages. Do not send messages
                        if undefined (default: None)
  --sender SENDER       Sender email address for sending messages (default:
                        restore_net_use.py@quark)
  --recipients RECIPIENTS [RECIPIENTS ...]
                        Recipient email addresses for sending messages
                        (default: None)
  --testmail            Log and send a test message (default: False)
  --onebyone            Restore connections one by one for debugging purposes
                        (default: False)

Use Windows Task Scheduler to schedule a script to run at boot. The script's parameters can be read from a file, making it easy to tweak them. Add a task and:

• On the General tab set it to run whether the user is logged on or not and with the highest priviliges
• On the Trigger tab add a trigger At Startup
• On the Actions tab add action Start a program with:
  • Program/script containing <PATH_TO_PYTHON>\python.exe and
  • Add arguments (optional) containing <PATH_TO_SCRIPT>\restore_net_use.py @<PATH_TO_OPTIONS_FILE>\restore_net_use.opt

Alternatively you can start the task at user logon for per-user shares.

Here is an example of an options file, restore_net_use.opt used on the author's system

--conntimeout
600
--logfile
d:\temp\restore_net_use.log
--smtp
mail.zag.si
--recipient
jan.kalin@zag.si

The script returns 0 on successful exit, 1 on errors.