It is often said that debugging is part of programming, and through error messages, the programmer can easily identify where there are problems in his/her code. But as you can see from the above screenshot the VBA Error 400 is one of those annoying types of error that does not give you any information on the origin of the bug of your code.
You only know that there is an error because you see the red cross on the message box with the number 400 referring to the error number. If as a VBA coder you have come across the VBA error 400 and do not know what to do, then this article is for you.
In the following article, we shall see the possible causes of this error (there are many of them) and how to fix them.
What Are the Causes of VBA Error 400?
Excel error 400 occurs when Microsoft Excel fails or crashes while running. This can be caused by many factors. The following are the most common:
Infected download or deficient installation of Microsoft Excel software
Invalid registry entries
Windows system files or Microsoft Excel-related program files infected by malware or a virus
Microsoft Excel-connected files maliciously or wrongly deleted by another program
Error in a macro; or the macro that you are trying to run is corrupt
Attack on the device or disk storage system including the MS Excel related data files and folders by malware or virus
Note: VBA 400 error messages can arise in any of the following Microsoft Windows operating systems: Windows 10, Windows 8, Windows 7, Windows Vista, Windows XP, Windows ME, Windows 2000.
How to Fix Microsoft Excel Error 400
The VBA 400 error message does not give any indication on the origin of the error. Consequently, you might have to try one or a combination of the methods below to fix the problem. However, I strongly advise you to check your macro very well to be certain that the error is not coming from the code itself before attempting any fix.
Transfer macros to a new module
Step 1: Select the developer tab on the Excel menu and click on the Visual Basic option or Click on Alt + F11 simultaneously.
Step 2: Select the Insert tab of the VBA Editor and click on the Module option or click on Tools > Macro then name the macro and press Enter
Step 3: Paste the VBA code that you want to use.
Step 4: Navigate to the File menu and click on Save Global.
Note: Make sure to delete the old module.
Switch on Trusted Access to VBA
Step 1: Select the Developer tab on the Excel menu, go to the Code group and click on Macro Security.
Step 2: Under “Developer Macro Settings" check “Trusted Access to the VBA project."
Other More Advanced Methods
If the solutions above have not solved your problem, then you should resolve to try the ones below.
Warning: If you are not versed in registry manipulation and related activities, I suggest you work with an expert on these solutions.
Scan your device to remove harmful malware and viruses from the system.
Remove system junk files and corrupted cache data.
Next, update the PC with the latest system drivers.
Try to “undo" all the recently made changes to the device through Windows System Restore files.
Uninstall each suspicious application, including the corrupted MS Excel app. Then, reinstall a fresh version.
Next, run the Windows System File Checker (SFC) scan to detect and delete corrupted system files.
Now, install the latest Windows OS update.
Finally, run a clean installation of Windows.
Beside the manual solutions explained above, there is also an automatic solution called the MS Excel Repair Tool. It is a highly recommended and one of the most appropriate tools to repair all sort of issues, corruption, errors in Excel workbooks. Just by scanning once, the tool detects and fixes various errors in Excel file and repair and recover damaged, corrupted or even inaccessible Excel file as well.