If Chem4Word appears to be installed correctly but does not start, please verify that Chem4Word has not been disabled by Word.

Adobe Acrobat Pro has been known to prevent earlier versions (prior to V3.1.6) starting up and thus being disabled and once in this state it is “sticky” until manually unblocking it.

You can check this by going to word options.

Click on Add-Ins [1], select “Slow And Disabled Add-ins” [2], then click on Go

If Chem4Word is showing in this list please select it then click on enable.

It is also worth checking the list of Disabled Items as well select “Disabled Items” [2], then click on Go

If Chem4Word is showing in this list please select it then click on enable, by clicking on steps and 5 as shown below.

After re-enabling Chem4Word you may need to restart Word to get the Add-In fully working.

If all else fails we have a PowerShell script at Get-Back-To-Square-One.ps1 which you can run to force remove Chem4Word. NB: This will NOT alter any documents that have chemistry in them.

After this you should restart your computer, then re-install Chem4Word by downloading the lastest setup. Please see https://www.chem4word.co.uk/download/ for instructions.

Version 3

Delete Registry Keys

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Office\Word\Addins\Chem4Word V3
HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Microsoft\Office\Word\Addins\Chem4Word V3
HKEY_CURRENT_USER\Software\Chem4Word V3

Delete Folders

C:\Program Files (x86)\Chem4Word V3
C:\ProgramData\Chem4Word.V3
C:\Users\Owner\AppData\Local\Chem4Word.V3

Version 2

Delete Registry Keys

HKEY_LOCAL_MACHINE\Software\Microsoft\Office\Word\Addins\Chemistry Add-in for Word
HKEY_LOCAL_MACHINE\Software\WOW6432Node\Microsoft\Office\Word\Addins\Chemistry Add-in for Word
HKEY_CURRENT_USER\Software\Chem4Word

Delete Folders

C:\Users\Owner\AppData\Local\Chemistry Add-in for Word

The ChemDoodle Web 8.0.0 editor requires Internet Explorer 11.

This error has only been seen on PCs which are not running Windows 10.

There are a couple of ways to fix this :-

1. Upgrade to IE11
2. Switch to using the ChemDoodle Web Editor 7.0.2, which requires Internet Explorer 9 or above.

If you have IE11 and are getting this error it may be due to corrupted ChemDoodlw Web settings.

To reset them:-

1. Click on the “Options” button on the Chemistry Toolbar
2. Select the “Maintenance” tab
3. Click on the top “Open” button to open the settings folder
4. Delete files (if present) :-
   Editor.html
   Chem4Word.js
   Chem4Word.css
   ChemDoodle-Web-702.txt
   ChemDoodle-Web-800.txt
5. Delete the folder (if present) :-
   ChemDoodleWeb

Could not load file or assembly ‘System.Data, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089’ or one of its dependencies. The module was expected to contain an assembly manifest.

This error is caused by an missing file (which is part of the .Net Framework) on your computer.

It most likely happened durung the un-installation of another program, which has incorrecltly removed the file.

Microsoft have a tool which should be able to repair your installed version of the .Net Framework.

This can be downloaded from https://www.microsoft.com/en-gb/download/confirmation.aspx?id=30135

Exception Font ‘Arial’ does not support style ‘Regular’.

This error is caused by an missing font file on your computer.

It most likely happened durung the un-installation of another program, which has incorrecltly removed the file.

Easiest way to fix this is to copy the font files from another computer

1. Steps to copy the font from one computer to another
2. Click on Start.
3. Go to Control Panel.
4. Click on Fonts.
5. Select Arial fonts and copy it to your flash drive.
6. Put the flash drive to the computer where the font is corrupted and paste it under Fonts folder.