How to fix a messed GP file association ?

Ever since I’ve worked with Dynamics GP I come across from time to time with systems where the extension association with Dynamics GP files is messed, more frequently this was happening on x64-bits systems (Windows 7-10, Server 2012 & up).

MVP fellow Mariano Gomez had posted about this back in 2009, and this would bug me because you couldn’t check quickly anymore what the version & build of a particular dictionary was when hovering over with the mouse or when opening the file properties, as there would an important tab gone missing (Dictionary).

My good friend David Musgrave had posted something about how to fix that many years ago in 2009 and I bumped into a 2011 community thread about the very same topic, but to me both posts where either incomplete or confusing in their instructions. Sure, David provided a file to fix the problem with one mouse click (or so he though), but it’s an incomplete solution.

How does it start ?

When you’re open the Dynamics GP folder on your computer or server, you’d see something like the capture below, where the .DIC files would look like they would be a notepad text file.. More than often that’s the association the happens to various GP files, including the .SET launch file because in Windows 10 for example if you double-click on the file and the system doesn’t know what to do with, a user would pick the notepad to peek into the file and then eventually by accident the extension would get associated permanently with Notepad or Wordpad text files..

Invalid file association

What it should look like !

After a regular pristine GP client deployment, this is how the dictionary association would look like below. Notice the file type in Windows Explorer shows “DIC File” and when you hover the mouse over the file name, it would provide you details about the Dictionary builder (ISV) and version / build numbers.

Proper file association

Also, when right-clicking on the file to open properties, you should see an additional tab that isn’t there for regular files (Dictionary) that provides you details about the relationship with GP. The advanced detail pane would provide information about the GP main build and allows you to see its relationship in the DYNAMICS.SET launch file, as sometimes the names are hard to identify when searching the Forms & Reports dictionaries.

File Properties / Dictionary Tab
Advanced properties

How do I fix it ?

This Microsoft article explains how to use a registry file (.reg) to make changes to the Windows registry which holds all the information for the file associations (and much more), so be very careful when using this. This other MS KB explains how to do a quick full backup of your Registry before doing any changes. Like with SQL databases, it’s always a good idea to make a backup before doing any changes that could modify your system’s behaviour

Basically a .REG file is a set of labels & values which represents the branches and fields in the registry. I’ve always thought of the .REG files to add values to the Registry, but it turns out you can also delete entries with it. Based on my findings and experience, as most of the corrupt entries have to deal with Notepad or Wordpad association, I’ve tweaked a registry file that will take care of removing the invalid entries and fix the proper values for the .DIC, .CNK & .SET file extensions. The file can be downloaded from this link (as the free WordPress blog does’t allow for file embedding).

If you’re curious to see what’s currently in your own registry, open the Registry Editor in Windows : WIN-key + R and then type “regedit.exe” (whiteout the quotes). Navigate to the following branch or simply press F3 to open the search box to look for “.DIC” : [HKEY_CLASSES_ROOT > .dic]

If you keep searching with F3 or move to this other branch, you’d see the other .DIC extension entry : [HKEY_CURRENT_USER > Software > Microsoft > Windows > CurrentVersion > Explorer > FileExts > .dic], There are at least 2 or 3 entries under that branch, in which you can see the association with Notepad or Wordpad.

The 2nd branch will be the link back to the first .dic extension entry you saw in the registry under HKEY_CLASSES_ROOT :

In order to run properly the registry fix file that is linked in the blog post, you have to open a command prompt with elevated privilege (Admin mode), otherwise the changes may not be applied if you lack proper permissions. Press the WIN key on your keyboard and type CMD in the search box, windows should show you the icon for cmd.exe on which you’d right-click with the mouse and then click on “Run as Administrator”.

in Windows 7
or in Windows 10 / 2012

When the command prompt is open, navigate yourself to the folder where you saved the “Fix DynGP Dictionary Association.reg” file and type : regedit Fix_DynGP_Extensions_Association.reg

Press Enter and you’ll be prompted by Windows to merge the content of the .reg file with your system registry :

Click on Yes and you should get a confirmation pop-up that the content was successfully merged. If you get an error message, then it’s likely that you don’t have the proper permissions. Ask your IT staff to help you with fixing this extension issue in GP.
Until next time.


3 thoughts on “How to fix a messed GP file association ?

Add yours

  1. This post is great and I learned quite a bit, but in my testing I think you can just get rid of all 3 user-specific file extension association keys for .cnk, .DIC, and .SET:

    Windows Registry Editor Version 5.00




    Which will revert to OS default, which should be correct (I don’t think there’s a way to much that up). Curious of your thoughts on that.


    1. Hi Lance,
      Thanks for asking the question.. I’ve actually checked on my older GP 2013 demo instance and there the association with the .DIC file was clearly broken. I just opened the Registry and checked the branch entries you listed and all but the .SET were absent from the Registry, which shows that the system doesn’t automatically re-associate them. I’m not aware of any apps doing this ‘magically’ in Windows.. Windows does need you to associate an extension with the apps. The entries are created when you install GP, though a repair might actually fix it too. Now, there is this “_Auto_file” option in the windows registry that allows the OS to pick up ‘smartly’ the best apps to fit a file extension (read possibly the next that opens it?). I don’t know for sure how that mechanic works, as I’m not a system developer, but to me that would be the best explanation.


Leave a Reply

Please log in using one of these methods to post your comment: Logo

You are commenting using your account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Website Powered by

Up ↑

The personal blog of Mark Polino

Erik Svensen - Blog about Power BI, Power Apps, Power Query

Blog about Power BI, Power Apps, Power Query

Freddys blog

Learn something new... - then Teach someone!

Life Hacks 365

Microsoft Dynamics & Microsoft Office Tips & Tricks

Vicky Rodgers - Microsoft Dynamics 365

Everything Microsoft Dynamics 365 for Customer Engagement


Stuff about the Microsoft Power Platform and Dynamics 365

The Dynamics Explorer

Exploring the World of Microsoft Dynamics ERP

Paul S. Randal

My contribution to the never ending Dynamics GP journey

%d bloggers like this: