Onenote - Reducing Storage Footprint on PC

Solution 1:

You may modify some settings of OneNote 2016 to reduce disk space usage.

By default there are two separate backup copies, so every notebook will need triple the amount of space. This can be changed in File > Options > Save & Backup, under "Number of backup copies to keep". The default value of 2 can be changed to 1, reducing the space by one third.

All OneNote data is by default kept on the system drive. If you have an additional disk or partition, you may direct OneNote to use it instead.

For every currently opened notebook, there is another copy created on the local cache in a special cache folder. By default this is C:\Users\<your name>\AppData\Local\Microsoft\OneNote. This may be changed in File > Options > Save & Backup, under "Cache file location settings", by clicking the "Modify…" button.

Note: Moving the cache to a removable drive or network location is not recommended.

Solution 2:

A review of Microsoft's help files did not find a configuration to reduce notebook file sizes by only fetching notes and attached files as needed, but did show OneNote stores PDF files as images which can cause file sizes to balloon. If you save PDF files a lot, you may consider just saving their content instead.

For your use case of saving recordings, I was unable to find any way to reduce sampling rate or bandwidth to reduce the size of the WMA files which will be stuck into the cache, so it's time to make a use case to your CFO for a second drive or larger system drive (NVMe preferred, SATA SSD if not practical) in your PC.

Solution 3:

I managed to free up 8gb of storage space.

Building on the solution offered by harrymc I first changed the location of the backup folder off of the local drive and onto a network folder. I then went back into the settings to performed a full backup to the new location:

File > Options > Save & Backup > Back Up All Notebooks Now

Depending on the size of your notebooks this may take quite a while.

Once the notebooks were backed up, closed each of the open notebooks. I then went to the Onenote folder on the hard drive and deleted the cache and back up folders (making a copy first just in case).

C:\Users\yourname\AppData\Local\Microsoft\OneNote

Finally I reopened the notebooks.

When the files were repopulated locally what I was left with was a single folder taking up 600mb. This was in place of two folders that were holding almost 11gb of data. A vast improvement.

Solution 4:

OK --- Now I DO understand. This is definitely a case where they don't manage or adapt their own storage well, nor make it easy for you to manage.

Here's one way to better manage space within OneNote, at least with 2016 version: --Each "Notebook" has it's own storage, and is chosen to be "available" (cached) or not. This means that you can limit your computer to only the notebooks that you want available offline. Then, only put things you know you will want offline in that Notebook. I'm assuming that you can also access OneNote on another PC, and manage all the Notebooks there. If not, use the Web Version of OneNote, as I explain below.

If you want to access files or data that is not in one of your cached Notebooks, then use the free Web Browser UI, with works fairly well to just read, and not create new content. You can also use the O-365 version for Android or iPhone, which is also free to access these Notebooks. (Check with the phone versions how they treat storage, or you might have to just use the browser's option, and not their apps.

Limiting and trimming files and photos is definitely going to save space. If copy and pasting from a web page for instance, each picture will generally be saved in the page. This can add up quickly. I personally trim out as much as the useless files, text and formatting from within the editing page.

Versioning and control is a major feature within OneNote, so you can always go back quite far and track what you did months, or even years ago. This is another reason for the large size. You can trim these back, especially in very large "Pages", by simply copying the old page with the history, and then deleting the original "Page". Be careful though, since they will have IDENTICAL names, and the content will also look identical--one with history and one without.