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The Confluence server must have the Graph Visualization Software (Graphviz) package installed in order for the Graphviz Diagrams for Confluence macros to work. The Graphviz package is free and supports a variety of operating systems including those supported by Confluence. 

Downloading Graphviz

Before you can use Graphviz Diagrams for Confluence, you will need to download and install Graph Visualization Software (Graphviz) on the system where you are running Confluence.  Download the correct version of the software that matches your environment.  You can find the available versions on the Graphviz Downloads page.  Once the download is complete then following the instructions below for your operating system. 

Graphviz on Windows

1. Download the installer from this link
2. The default installation path will be C:\Program Files (x86)\GraphvizX.XX\bin (Example: GraphvizX.XX → Graphviz2.38)

3. Open cmd window as administrator and go the location C:\Program Files (x86)\GraphvizX.XX\bin and run the below command:

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   dot.exe

   
   

4. Exit the command window.

5. Go to the Control Panel →  System and Security → System, and on the right side navigation panel, you will see the link Advanced systems settings.

6. Once there in advance settings, a dialogue box will open which will show the button Environment Variables. Click on the button Environment Variables.

7. Select the entry "Path" on the system variables section and add C:\Program Files (x86)\GraphvizX.XX\bin to the existing path. Please see the below screenshot for reference.                                     
   Note: Please make sure you add ";" at the PATH which is already existing under User Variables and mention the path C:\Program Files (x86)\GraphvizX.XX\bin. Also please add a New path on the system variables section and add the Path C:\Program Files (x86)\GraphvizX.XX\bin

8. Click on Ok Button. 
9.  Restart Confluence from a new cmd window.
10. Go to the system information page on confluence instance.
11. Verify if you can see C:\Program Files (x86)\GraphvizX.XX\bin on "Path" attribute on system information page in confluence.
12. If the path is available, that means that the configuration changes are successful. 
13. Go the page where you have used the macro and verify if the add-ons work.
14. Restart Confluence

15. Verify it works by creating a page with a simple flowchart macro like:

    
    

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    {flowchart} A -> B {flowchart}

    
    

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1. In the download link here from Graphviz we see that 2.38 as the latest version, but as of today 2.43.x is the latest version for Windows.
2. Graphviz team will soon make it available on the web as per the references1 and reference2.
3. We followed their suggestion and keeping the latest exe and missing config i.e graphviz-2.43 file in this page.
4. So, you need to install the exe and copy the config6 file in the bin folder after successful installation.
5. After the installation is completed follow the steps 7-15 mentioned above with the latest version of the graphviz. Check dot -V to check the version at the command prompt whether you changes are reflected.
6. As we are finding some performance issues with 2.38 version of the Graphviz for Windows, we are adding this section as temporary until the latest version is on the Graphviz Downloads location.

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1. Follow the instructions mentioned here.
2. The installer should set up everything so that the dot  appears under on the path 

Graphviz on Linux and Unix

1. Install the graphviz.rpm, the graphviz-graphs.rpm, and the graphviz-gd.rpm packages
2. Open the directory GraphViz is installed under and confirm the path
3. Log in as the user who runs Confluence or starts the Confluence service
4. Append the path to the bin directory of GraphViz to the 'Path' variable

Last resort

The method mentioned in this section is not required and not recommended in most cases, but, if you can't get your path set correctly to find the dot executable, then this is an alternative. 

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