jameswebb68 · August 31, 2025 09:30 · Chris-T2B · Jan 15, 2020 · vapour1ze · Oct 30, 2020
diff --git a/gistfile1.ps1 b/gistfile1.ps1
 # Your NAS Synology device suddenly lost connection to your Windows Domain Controller, and or intermittent AD connectivity issues.
 # Symptoms include but not limited to: 
 # - Failing to rejoin after removing the account on the Domain. 
 # - Failing to rejoin without any changes
 # - Join attempt results in = "Failed to join the Windows domain. Please check your domain and firewall settings and try again"
 # - Synology is joined, but attempting to connect from domain clients results in "There are no logon servers available to service the logon request"
 # - This problem happens intermittently, sometimes rebooting the Synology device allows you to rejoin (Not a solution). 
 # - Sometimes rebooting both Synology device and Domain Controller allows you to rejoin (Not a solution).

 # 1st.) *OPTIONAL* Remove the AD Synology device from Avtice Directory Users/Computers.
 #       Step could be required if your Synology system is currently in a disconnected state.
 #       ie: Inaccessible from Domain systems, and or "no login servers available".
 #       Always try Step 2 first, you have nothing to lose. Permissions for Domain Users/Groups, entered
 #       on your Synology system, for shared folders do not get removed when the Synology Computer object
 #       is deleted from the Domain's Active Directory Users/Computers.

 # 2nd.) *THE FIX*) Enable SMB1 Protocol - Try the following commands on your Domain Controller:
 #   Use the appropriate commands for the terminal/console/shell you are using.
 #   Goal: Enable SMB1 and restart LanmanWorkstation and LanmanServer SMB Windows services

 # powershell v4 (ws2012+)
 Set-SmbServerConfiguration –EnableSMB1Protocol $true
 # powershell v2 (ws2k8)
 Set-ItemProperty -Path "HKLM:\SYSTEM\CurrentControlSet\Services\LanmanServer\Parameters" SMB1 -Type DWORD -Value 1 -Force
 # cmd (cmd/run)
 reg.exe ADD 'HKLM\SYSTEM\CurrentControlSet\Services\LanmanServer\Parameters' /v SMB1 /t REG_DWORD /d 0x1 /f

 # restart SMB services (Powershell)
 Restart-Service LanmanWorkstation -Force; Restart-Service LanmanServer -Force
 # restart SMB services (cmd)
 net stop LanmanWorkstation & net start LanmanWorkstation
 net stop LanmanServer & net start LanmanServer
 # sc cmd method
 sc stop LanmanWorkstation & sc start LanmanWorkstation
 sc stop LanmanServer & sc start LanmanServer

 # 3rd.) Enjoy the problem never happening again. You might also want to setup a WINS server, since Synology boxes seem to function
 #      much better with one available to them.

 # Info: Why would SMB1 all of a sudden be relevant to a previously joined device with it disabled? No Clue.
 # Since I don’t use SMB for anything on the related Domain Controller, I now schedule a task to restart SMB services
 # once a day. If the problem persists you may want to evaluate your Domain's Network Permissions (Securty Settings)
 # for NTLM authentication. I can see this being an issue for certain environments. Might want to look into adding an
 # server exception for your NAS. Granted i have not tested a Synology with zero NTLM (no NTLMv2 only Krb). I am also not sure
 # what data is passed from NAS to DC in regards to SMB1. Somepoint i will setup a lab and capture data with SMB1 enabled/disabled,
 # and the activity of the synology system in a dissconnected domain state.
	# Your NAS Synology device suddenly lost connection to your Windows Domain Controller, and or intermittent AD connectivity issues.
	# Symptoms include but not limited to:
	# - Failing to rejoin after removing the account on the Domain.
	# - Failing to rejoin without any changes
	# - Join attempt results in = "Failed to join the Windows domain. Please check your domain and firewall settings and try again"
	# - Synology is joined, but attempting to connect from domain clients results in "There are no logon servers available to service the logon request"
	# - This problem happens intermittently, sometimes rebooting the Synology device allows you to rejoin (Not a solution).
	# - Sometimes rebooting both Synology device and Domain Controller allows you to rejoin (Not a solution).

	# 1st.) OPTIONAL Remove the AD Synology device from Avtice Directory Users/Computers.
	# Step could be required if your Synology system is currently in a disconnected state.
	# ie: Inaccessible from Domain systems, and or "no login servers available".
	# Always try Step 2 first, you have nothing to lose. Permissions for Domain Users/Groups, entered
	# on your Synology system, for shared folders do not get removed when the Synology Computer object
	# is deleted from the Domain's Active Directory Users/Computers.

	# 2nd.) THE FIX) Enable SMB1 Protocol - Try the following commands on your Domain Controller:
	# Use the appropriate commands for the terminal/console/shell you are using.
	# Goal: Enable SMB1 and restart LanmanWorkstation and LanmanServer SMB Windows services

	# powershell v4 (ws2012+)
	Set-SmbServerConfiguration –EnableSMB1Protocol $true
	# powershell v2 (ws2k8)
	Set-ItemProperty -Path "HKLM:\SYSTEM\CurrentControlSet\Services\LanmanServer\Parameters" SMB1 -Type DWORD -Value 1 -Force
	# cmd (cmd/run)
	reg.exe ADD 'HKLM\SYSTEM\CurrentControlSet\Services\LanmanServer\Parameters' /v SMB1 /t REG_DWORD /d 0x1 /f

	# restart SMB services (Powershell)
	Restart-Service LanmanWorkstation -Force; Restart-Service LanmanServer -Force
	# restart SMB services (cmd)
	net stop LanmanWorkstation & net start LanmanWorkstation
	net stop LanmanServer & net start LanmanServer
	# sc cmd method
	sc stop LanmanWorkstation & sc start LanmanWorkstation
	sc stop LanmanServer & sc start LanmanServer

	# 3rd.) Enjoy the problem never happening again. You might also want to setup a WINS server, since Synology boxes seem to function
	# much better with one available to them.

	# Info: Why would SMB1 all of a sudden be relevant to a previously joined device with it disabled? No Clue.
	# Since I don’t use SMB for anything on the related Domain Controller, I now schedule a task to restart SMB services
	# once a day. If the problem persists you may want to evaluate your Domain's Network Permissions (Securty Settings)
	# for NTLM authentication. I can see this being an issue for certain environments. Might want to look into adding an
	# server exception for your NAS. Granted i have not tested a Synology with zero NTLM (no NTLMv2 only Krb). I am also not sure
	# what data is passed from NAS to DC in regards to SMB1. Somepoint i will setup a lab and capture data with SMB1 enabled/disabled,
	# and the activity of the synology system in a dissconnected domain state.