How to correct Error Code 1400L Invalid Window Handle

Backup failed due to Error Code 1400L invalid window handle; how do I fix this?

Question Info

Last updated September 12, 2019 Views 11,893 Applies to:

Hi Tony,


I understand how it feels when you receive an error while trying to perform backup. I will be happy to help you with this issue.


Let’s try the following troubleshooting steps; I am sure this will help you resolve the issue.

Step 1: System File Checker (SFC)

SFC tool scans system files and replaces incorrect versions of the system files by using the correct versions.

To run the System File Checker tool, follow these steps:

a) Click Start, and then type cmd in the Start Search box.

b) Right-click cmd in the Programs list, and then click Run as administrator.

If you are prompted for an administrator password or confirmation, type your password or click Continue

c) At the command prompt, the following line, and then press ENTER:

sfc /scannow

How to use the System File Checker tool to troubleshoot missing or corrupted system files on Windows Vista or on Windows 7?


Step 2: I would suggest you to keep the computer in clean boot mode and try performing the backup then check if the issue persists.

A clean boot helps to verify if any third party application services or startup item is causing this issue.
You may refer the following KB article to set the computer in clean boot:
Note: After the trouble shooting steps, refer to Step 3 from clean boot link to set the computer back to normal start up mode.
I hope it helps. If you have any issues in future please let us know. We will be happy to help you.

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