Windows cannot access file server

Question

I have recently upgraded my computer and now cannot access the Buffalo Terastation TS3400D series.

I keep getting the message Windows cannot access file server xxx Error code 0x80070043

Please help

Answer 1

Hi Anni,

This error is very often caused by the Windows upgrade disabling the legacy SMB1 client while older Buffalo TeraStation firmware still negotiates only SMB1. The quickest way to confirm that is to temporarily turn on the SMB 1.0/CIFS Client, test access, then plan the permanent fix.

On the upgraded PC, open Start and type Windows Features, then choose Turn Windows features on or off. In the list, expand SMB 1.0/CIFS File Sharing Support and tick SMB 1.0/CIFS Client, then click OK and restart Windows. After the restart, press Win+R and enter \\terastation-name or \\ip-address to try the share again.

If you prefer a single command, run PowerShell as administrator and use:

Enable-WindowsOptionalFeature -Online -FeatureName SMB1Protocol-Client -NoRestart
Restart-Computer

If the share opens after this, we have confirmed the cause. The long term fix is to update the TS3400D to firmware that supports SMB2 or SMB3, enable SMB2 or SMB3 on the NAS, then turn SMB1 back off on Windows with:

Disable-WindowsOptionalFeature -Online -FeatureName SMB1Protocol-Client -NoRestart
Restart-Computer

Tell me what happens after you enable the SMB 1.0 client and try the UNC path. If it still fails, I will guide you to the next step.