The Grunt tab can disappear for a variety of reasons, but it's almost always one of three. Let's look at each in turn.
We've automated a lot of the information found in this support article. Before continuing with the steps in this guide, try to run the automated tool found here: https://support.grunt.pro/hc/en-us/articles/360008586318
Grunt is not installed
To check if Grunt is installed, you need to look at your installed programs. Open your start menu, and search for "Add or remove programs"
Open that app. You should now see a view that lists you installed programs. Now search for Grunt in the list. If Grunt is installed, you should see something like this:
If you do not see Grunt in the list, Grunt is not installed. Head over to https://www.grunt.pro/download to get the latest version.
PowerPoint has disabled Grunt
This can happen if PowerPoint crashes or something or other goes wrong under the hood. We won't bore you with the technical details, but suffice to say that sometimes PowerPoint can be a bit aggressive in disabling add-ins.
By the way, if PowerPoint ever prompts you if you want to disable an add-in, the answer is usually no.
To see if Grunt has been disabled, you can view all your add-ins by opening File and Options. You'll normally find File to the left of the Home tab.
The Options button is located all the way to the bottom left of the File tab.
You can also open the options menu by clicking Alt+F+T.
A dialog will now appear. Click the "Add-ins" section.
You will now see the following view. If Grunt is disabled, it will appear in the list of disabled add-ins.
You can double check by clicking the drop-down to the right of where it says "Manage", changing to "Disabled Items and clicking "Go". You should now see the following dialog:
If Grunt is indeed disabled, you will find it in this list. Click it and now click the button marked "Enable". Now, either Grunt will activate by itself, or you must restart PowerPoint. By the way, if PowerPoint prompts you to disable Grunt next time you open PowerPoint, remember to say no!
It may still be the case that the Grunt tab does not appear. In that case, you way need to activate it (yes, that is not the same as enabling it). To do that, follow the steps in the following section.
Grunt is inactive
An add-in can be inactive or disabled. To see if Grunt is disabled, follow the steps in the previous section. If Grunt is inactive, you will find it in the list of inactive add-ins in the COM add-ins dialog. To open that dialog, follow the steps described in the previous section. This time, rather than opening the "Disabled Items" dialog, open the COM Add-Ins by clicking "Go".
If Grunt is disabled, it will appear without a check mark in the list of COM Add-ins.
Click it so a check mark is added and the click OK. After a couple of seconds, the Grunt tab should appear. If it doesn't, restart PowerPoint.
None of the above steps worked for me
First, we recommend that you retry the steps above. You may have made a mistake. Also - and this is key - PowerPoint will sometimes ask you if you want to disable a particular add-in when you open it. If you get such a prompt, choose No. If you choose Yes, PowerPoint will disable the add-in in question, and you will have to redo the steps in the "PowerPoint has disabled Grunt" section above.
If none of the steps above work, we recommend that you restart your computer. Sometimes, instances of PowerPoint may be running in the background and creating problems. If that doesn't help, we recommend the you uninstall and reinstall Grunt. Go to https://www.grunt.pro/download to get the latest version.