Recently, a customer I work with asked me to investigate why the tabs in their shared OneNote notebooks were disappearing. It is especially prevalent when they moved to OneNote 2016. The cause as it turned out was something called Windows Deduplication. At its simplest, it is a way to reduduplicate files and similar streams of data on a disk. It is a form of compression at its simplest which is to say it is a mechanism to allow you to stick more stuff on a computer or server disk. What we found was the deduplication was corrupting the OneNote index (toc) on the server and each time someone went to make changes to the OneNote file on the server. Tabs would start disappearing for other users when multiple users were editing the files. When we enabled the exception for OneNote files in the data deduplication feature and then moved the OneNote files from one folder to another and then back (which is required to de-optimize the files), the problem went away. To resolve this problem you will likely need your administrator involved:
- You will need to set an exception for the OneNote file extensions in Windows Server 2012 Data Deduplication.
- Here are some details on configuring that with PowerShell. See the “Modifying Data Deduplication volume-wide settings” section.
- You will need to exclude these extensions: *.one, *.onebin, *.onetoc2
- Next, have everyone close OneNote on their systems.
- Finally, you will need to “deoptimize” (or, and I love this, de-dedup) the files. To do this, you will create a folder somewhere in the shared folder, move all the files in the OneNote folder to that location, then move them back.
NOTE: Nothing needs to be done on the clients, they will just work the next time the users launch OneNote. You might notice the tabs will still initially appear to be missing, but they will re-index and come back. This might take a few minutes depending on how many tabs there are.
Once completed, you should find that your tabs are no longer disappearing.
Thanks for this article, it descriubes the situaiton I am in closely. Though, in my situation, the files are stored locally on comptuers instead of a server for portability purposes. How would you address this issue when the files are stores on a Windows 7 computer?
Just had a related scare. A folder within a OneNote Notebook saved on a server location designated for individual use only, seemed to disappear as didn’t see the tab anymore. Also couldn’t locate it by adding terms it contained in the OneNote Search window. Tried navigating through various notebooks. Nothing worked. Closed OneNote and reopened it. The folder was back. Which makes me wonder about ways to backup OneNote and how frequently.
Thanks for this article, it describes the situation I am in closely. Though, in my situation, the files are stored locally on computers instead of a server for portability purposes. How would you address this issue when the files are stores on a Windows 7 computer?
I have not encountered that issue before, but it might be similar if there is some type of shadow copy service or another application that is locking certain files or changing them outside of OneNote. In situations like this it all depends on how easy it is to reproduce the issue – consistently. If you can reproduce it easily, then you run MSCONFIG and start turning off half of everything until the problem goes away, then slowly turn back on things until the problem returns and then you find your culprit. If it is not easy to reproduce the issue then you will probably be a trial and error in working with the files to see what might be common about the issue when it occurs. I wish I had a simple answer for you, but the one in this blog took a very (very, very) long time to resolve.
“took a long time to resolve” – was it actually resolved? What you describe (turning data duplication off) is a workaround. Microsoft should really fix that file corruption in the first place. Did you report it as a bug?
It has been reported as a bug. Yes. It is not completely a problem with OneNote but how multiple OneNote sessions interact with the index and how deduplication attempts to reconcile the changes. I am not 100% versed on the technical details, but I do know that it is being looked at.
@ DAVECRA: being looked at? it has been almost 2 years ago since you wrote that answer and it still happens. Seems like it has not been happening and our tax money is going to what?
This is not a OneNote issue, per se. OneNote cannot change the way it creates its indexing or it will break all versions of OneNote out there. The problem is with how deduplication works (which also cannot be changed and is not just a Windows issue as many deduplication services are 3rd party). Nor is it how deduplication works against the OneNote index. The solution is simply to not deduplicate the drive where the file is stored, or move to OneDrive.
All current development focus for OneNote as far as I can tell is now directed at working online from OneDrive. In addition, the full desktop application is slowly being deprecated. The Windows Store App will be replacing it. It is also no longer a part of Office. It is a part of Windows 10 going forward. So, unfortunately, even if there was a fix, it is likely that the product teams are no longer focused on on-prem implementations of OneNote.
There seems to be a setting to exclude a directory from dedup which will work fine for us as all our OneNotes are in a single folder on the file server. I have added the exclusion. Do you really need to move the files to another directory and then back again? How does that de-dedup them?
I forget as it has been many years since I found this solution. As best I can recall the reasoning had something to do with the state the files are. The move is to assure that on write-back the alternative data stream is “restored” to the original state otherwise even though the folder no longer duplicates the files, the files themselves still have the “flag” on them.