I was searching around for some lost files, another topic, when I happened to look in Arduino15 and found the preferences text file.
I have used it and changed it in the past for settings like indentation.
I decided to have a look, and noticed it looked different to what I had seen before, but I noticed it had credits by Elegoo and had been dated 21 May 2025.
I haven't been near it this year, let alone three days ago.
Where does the text file originally come from and could it be changed by a manufacturer like Elegoo?
I do use Elegoo boards, but not on this PC.
The occasions that I changed the file would have been on another PC and a much earlier IDE than the present 2.3.6.
Just to be sure, do you mean the file named preferences.txt? The .txt extension might be hidden if you have Windows File Explorer configured to hide file extensions.
If it is actually "credits", that would be unusual. Maybe you are only seeing the chance occurrence of the string "elegoo" in some of the preference data and incorrectly interpreting that as "credits". Please post the exact text from the file.
It is automatically generated by Arduino IDE 1.x.
Anything is possible, but I can't think of any reason they would do that. More likely you used a sketch that has "Elegoo" in its name or path and you are just seeing that in the recently used sketch history data that is stored in the file.
Once you provide the actual text from the file we will be able to answer your question with more certainty.
Note that Arduino IDE 2.x does not use the preferences.txt file in any way. It uses a completely different system for storing the preferences data. The file is specific to Arduino IDE 1.x.
It's definitely named preferences.txt in Arduino15
i have 1.8.19 and 2.3.6 on this PC
This is a copy of the Readme first part of the contents
"Dear Customer,
Thanks a lot for your support and purchasing Elegoo products.
Select the folder with your language. In that folder you will find:
A tutorial. Please read and follow it, or you may want to get the latest tutorial from our website, www.elegoo.com
A folder labeled "code" which contains example programs for many of the chapters in the tutorial. To use these examples, just click on the file named for the chapter (e.g. Lesson 4 RGB LED) and your Arduino application will launch with the sample program already in it, ready to upload. Remember you may need to update the Library!
A folder labeled Libraries, that contains additional libraries your Arduino software may need for certain applications. Chapter 1 of the tutorial explains how to use these libraries.
OK, that is indeed very strange. I don't have any explanation for how that content could have ended up in the preferences.txt file.
Another mystery is how the content could persist in the file. I added it to my preferences.txt file and when I started Arduino IDE it immediately automatically removed that invalid content from the file. Do you have your installation of Arduino IDE 1.8.19 configured in portable mode?
No. Haven't got one.
When I open it in Notepad, it doesn't look anything like like what I've seen before.
The Elegoo file has several headers in it with the Readme, a blink example or two and the preferences.
The IDEs were clean installs from the Arduino website.
I wouldn't install them from Elegoo or anyone else.
I've got several other PCs with the IDE on them, so I'll check those as well.
Sorry but you are wrong.
I've never bought a computer from eBay.
It was brand new direct from Dell.
As for omitting information, that's plain silly.
Got some suggestions what's missing?
Yes, indeed it's a mystery.
Despite the best efforts of the other contributor to muddy the waters, it hasn't arrived there by my actions.
I might buy Elegoo boards, but I don't go near their website to download anything.
Both IDEs, 1.8.19 and 2.3.6 came from Arduino official website.
As I said, it's not like a text file that I'm used to seeing.
It's based on Notepad which I open it with.
It has five tabs
"Readme first.txt"
"boards.txt"
"boards.txt"
"blink.txt"
"preferences.txt"
So, it's preferences.txt within preferences.txt
I had a look at the preferences.txt file on another PC and it's the normal file I would expect. No mention of Elegoo.
At the moment, the Elegoo version doesn't appear to be causing a problem, but do you think it worthwhile taking a copy of the "normal" preferences.txt file and replacing the Elegoo version?
The preferences.txt file does not have 5 tabs. What you are seeing is a recent change to Windows Notepad to support multiple tabs, one of which is allowing you to edit preferences.txt. The other tabs are accessing other, recently edited files
My other PC must still have the older version of Notepad on it.
I must admit I rarely use it.
The newer PC, about a year old, must have come with the new version bundled.
The Elegoo involvement remains a mystery.
I've only ever once altered the preferences file many years ago and was very wary of doing that.
I'm quite happy to upload the mysterious preferences text file to see if there are any other clues.
The gremlins are at work or it's a fiendish North Korean hacker.
As @UKHeliBob explained, only the "preferences.txt" tab will show you the contents of the preferences.txt file. The content you see in the other tabs are from completely different files that have no relation to the preferences.txt file.
Do you see the Elegoo text in the "Readme first.txt" tab?
Hover the mouse pointer over the Notepad tab that contains the Elegoo text. After a few seconds, a tooltip will appear that shows the path of the file which is providing the content of that tab. It is the file at that path that you are viewing in Notepad when you have that tab selected, not the preferences.txt file.
There is no need, because there is no "Elegoo version". If the unrelated file that contains the Elegoo text is bothering you, just click the X icon on that tab in Notepad to remove that file from Notepad.
It would have been a good next step if the mystery remained, but since the mystery has been solved there is no need. We would not see the Elegoo text in that file, so sharing it wouldn't serve any purpose.
Other than where did it come from, the Elegoo stuff
Yes, I was starting to wonder about the other tabs.
Of course, when you open Notepad now, you can see the new layout.
Are boards.txt located somewhere else?
Nd do they need to be up to date?
I will check the preferences.txt file in what I call the Elegoo version against the old Notepad version.
Thanks
There is a good chance the path of the file will provide the clue you need to solve that mystery.
Each Arduino boards platform has its own boards.txt file.
You will find them under subfolders of the C:\Users\****\AppData\Local\Arduino15\packages folder.
For example, if you have the latest version of the "Arduino SAMD Boards (32-bits ARM Cortex-M0+)" platform for the Nano 33 Iot board installed, you will find that platform's boards.txt file at this path:
There is one other location when you are using Arduino IDE 1.x. The 1.x installation includes a bundled copy of the "Arduino AVR Boards" platform. So you will find another boards.txt file under the hardware\arduino\avr subfolder of the Arduino IDE 1.x installation folder. However, if you have installed Arduino AVR Boards via Boards Manager, that installation is made in C:\Users\****\AppData\Local\Arduino15\packages\arduino\hardware\avr, and the copy of Arduino AVR Boards in that folder will be used instead of the copy bundled with Arduino IDE 1.x. The Arduino IDE 2.x installation does not contain a bundled copy of Arduino AVR Boards, so this confusing situation only occurs with 1.x.
They don't "need" to be, but it is generally a good idea to keep your Arduino boards platforms updated so that you can benefit from the fixes and enhancements made by the platform developers. Note that you must update the entire platform, which typically consists of many files, not the boards.txt alone. You can update your platforms using the Arduino IDE Boards Manager: