[German]I'm picking up an issue that a blog reader reported to me back in March 2023. While checking his temp folder under Windows, he noticed that there are several GByte-sized log files with the name Aria-debug-xxx. His guess is that Office or Microsoft Word in conjunction with OneDrive has something to do with it. I then did some more research and found that the problem with these log files is probably more common and has existed on Windows since at least 2017.

A reader note

I confess, I had not come across this issue before and I was a bit stunned when I got the mail from David on my desk at the end of March 2023. David wrote:

Hi Günter,

I noticed the other day that [there was] a bunch of several GB log files in my temp folder – Aria-debug-xxx where xxx stands for a random number.

Deleted those and thought nothing of it. Today I see MS Word is reading around at 100mb/s on my SSD and it's one of those log files, just a new one, which has since resurfaced.

The internet says: "the files are used for logging with Onedrive Errors". Well with me OneDrive is uninstalled and MS Office a LTSC version from the university, so cloud -free.

So WTF?! They fill my SSD with log files for an uninstalled feature. This is a mess, I can't find a way to turn this off on the internet except "reinstall onedrive" which is out of the question.

David suggested to mention the problem in the blog, in the hope that a reader may know a workaround.

Many mentions on the web

I had then times on the Internet searched for this topic and came across numerous hits to this log files. This post in the English-language Microsoft Answers forum from 2019 describes the same problem:

How are Aria Debug files created and what is their purpose?

They appeared after trying to sync my Extra One Drive to my D Drive.

Where are these files normally located on a computer?

what is there purpose?
Why can't I delete them?

Can they break my computer?

But a posted screenshot shows only two files with a size of 1-2 kByte – so not really a problem. With gigabyte-sized .log files, however, it looks quite different. In the forum thread in question, a community moderator replied and suggested performing a reset for OneDrive.

%localappdata%\Microsoft\OneDrive\onedrive.exe /reset

For example, in the German-language Microsoft Answers forum, there is this post from 2017 where someone made the same observation and wrote the following.

Large aria-debug file on my SSD

I have a huge problem with my SSD. Every day an aria-debug file is created there, which eats the memory of my SSD. As an example, currently the file is named aria-debug-5876.log which takes 28 GB of memory!

Of course I can delete it every day, but why is it created in the first place? How can I prevent it from being created? And by what is it being created? I really need urgent help :(

Then, from the concerned user, the above screenshot was posted with an excerpt from this temp folder showing the misery. There the log files are huge.

An analysis at askwoody

On askwoody there is a thread from 2021 with the same problem. There, user Rick Corbet went to the trouble of using ProcMon from the Sysinternals tools to analyze who or what is writing the log files. The conclusion was:

It looks like there are two culprits – OneDrive (which I have never logged into or ever used) and the built-in Disk Space Clean-up Manager for Windows utility.

The user has identified two culprits on his system. One is that OneDrive is causing these log files – the user never logged in there – which Microsoft's developers probably don't have on their radar and their code then runs amok, making the log files huge. And the user writes that the built-in disk cleanup utility for Windows is probably also involved in these log files. In the follow-up comments, the user writes that the .log files were all 0 bytes in size. The assumption is made that the .log files have something to do with telemetry and logging at OneDrive. The following screenshot, posted on Askwoody, shows the DLL files in question.

Source: Askwoody.com

However, the thread is fizzling out as far as an exact explanation regarding what generates the aria-debug files is concerned. This article posits that a faulty update also triggers the generation of aria-debug files – but I don't find that really convincing. But the article contains some hints what to try regarding the deactivation. Ingo Böttcher gives in the MS Answers forum thread from 2017 the recommendation, to move to the folder:

C:\Benutzer\<deinName>\AppData\Local\Microsoft\OneDrive\setup\logs

and delete the two following files:

userTelemetryCache.otc
userTelemetryCache.otc.session

and the log files within the folder. I don't checked, it that helps. What I have noticed, however, is that the problem has been bogging down Windows for at least six years without a convincing explanation or even a solution to stop the .log files from being created. A tragedy – or is anyone from the readership aware of a cause as well as a solution?