If your VPN connection is unstable, or if your configuration doesn’t fit the server’s requirements (for example, if you’re using Samba or an OpenVPN tunnel that restricts your bandwidth), you may encounter error 0x8007003b when attempting to copy a large file (more than 100MB).

Method 1: Turn Off Any Third-Party Security Software, Such as A Firewall or Antivirus Programme

Your computer’s security software has a history of conflicting with upgrades. Since antivirus programmes can’t tell the difference between legitimate and malicious use of these apps, they may suggest you ban them or even remove them.

Error 0x8007003b

To turn off your antivirus software, look for its icon in the lower right corner of your screen. Right-click the antivirus program’s icon once you’ve found it. To turn it off, select the option from the menu that appears. While you are updating, your antivirus will be disabled.

If you’d rather not turn it off and would prefer to avoid this issue in the future, putting up an exception in the antivirus programme is the best option. The standard procedure for creating a new exception in an antivirus programme entails navigating to the program’s Settings, locating the Exceptions section, and adding a rule.

If you need help with either of these, you may get comprehensive instructions on how to proceed by going to the website of the antivirus software you are using. Putting the firewall to sleep is as easy as following these instructions.

Step 1: To access the Settings interface, click the Start button and then click All Programs. Find the icon for the Control Panel and select it.

Step 2: You may access System and Security settings by selecting that icon in the Control Panel.

Step 3: Windows Firewall should be selected.

Step 4: If Windows Firewall is turned off, the Windows Firewall state will be Off. If it’s turned on, turn it off immediately.

Step 5: Select Turn off Windows Firewall in the Customize Settings window, then click OK.

Method 2: Ensure Proper Formatting

There are several file system formats included with Windows and its storage, including FAT32 and NTFS. This issue may be attributable to one or more of the drawbacks of both approaches. When copying a file, make sure the target drive is formatted correctly.

You should know that FAT32 can only handle files up to 4GB in size, and that it will crash near the conclusion of the copy if you try to copy anything larger. If you have many smaller files, you should be alright; this only occurs when one file is larger than 4GB.

If you stick to the procedures outlined above, you should have no issues despite the fact that this issue appears to be much more involved than it actually is.

Method 3: Windows Powershell Script For Enabling Guest Access

Error 0x8007003B may be resolved by modifying this value to enable Guest access on your Windows system; to do so, use Registry Editor; alternatively, you can use the command I’ve provided to enable Guest access without having to manually edit the registry.

Please read on to learn how to activate Guest Access.

Step 1: To launch Windows Powershell as an administrator, select it from the menu that appears when you right-click the Start button.

Step 2: Copy and paste the following command, then hit the enter key.

REG ADD HKLM\SYSTEM\CurrentControlSet\Services\LanmanWorkstation\Parameters /f /v AllowInsecureGuestAuth /t REG_SZ /d 1

Step 3: If restarting your machine fixes the issue, it will.