Fixing White Screen & "Add-in Could Not Be Started" Error

The situation

The Microsoft Word Add-in side-panel is a miniature browser (like Edge or Chrome) that runs PERRLA inside of Word. Just like Edge or Chrome, the mini-browser built into Word has different versions. Older versions of this mini-browser can have a hard time running newer applications like PERRLA – resulting in an error.

Here are some ways you can try to fix this error.

Confirming the Error

Before trying the fixes below, you should confirm that this is a problem with all Add-ins and not just PERRLA. Here's how:

1. Open a Word document. 
2. Try to open any of the PERRLA side panels. 
3. Right-click inside the white panel. 
4. If WebView 2 is installed, you will see a contextual menu with Back, Forward, Refresh, etc.
   If WebView 2 is not installed, you won't see a menu at all.

If you do not see the right-click contextual menu, you will need to install WebView 2 manually.

Step 1: Install WebView2 from Scratch

Here's how you can install WebView 2 manually from Microsoft.

1. Close all Microsoft Office applications (Word, Excel, Outlook, etc.). 
2. Download the WebView2 Installer: https://go.microsoft.com/fwlink/p/?LinkId=2124703
   If this package does not work in your configuration, install an alternative version. Browse this Microsoft resource for versions compatible with different MS Edge builds and x86, x64, or arm64 architecture.
3. Once downloaded, run the WebView2 Installer. 
4. Restart Word & try to use the PERRLA Add-in. 

If this worked, then PERRLA will launch like normal. If not, follow the additional instructions below.

Step 2: Reset WebView2 Files

If the WebView2 installation did not fix the issue, then we will need to run a command through Windows Terminal to force it to disable and reset the Add-in files for Word.

Here's how:

1. Close all Microsoft Office applications (Word, Excel, Outlook, etc.). 
2. Open Windows Terminal.
   If you do not have Windows Terminal or it won't open, you can install it from the Windows Store.
3. Run the following command – both lines.
   (Note: If you have customized your default Windows drive name, you will need to update the command to match the customized name.)
   
   powershell Add-AppxPackage -register -disable C:\Windows\SystemApps\Microsoft.Win32WebViewHost_cw5n1h2txyewy\AppxManifest.xml
    
4. Close Terminal. 
5. Restart your computer & launch Word. 
6. Open the PERRLA ribbon tab & click Settings.
   If WebView 2 is running properly, then PERRLA should launch and you should be able to see the contextual menu when right-clicking inside the PERRLA panel.

Once you have done this, the issue with the side panel showing a blank white screen should be resolved.

With that being said, if you're still only seeing a blank side panel in Word, you may simply need to reset your router/modem or reboot your computer.

If you are still having trouble, don't hesitate to reach out to our Customer Support team through the link below or directly via email ([e-mail]).