no headers files (.h) found

Using Arduino IDE 1.x
1

Invalid library found in C ...................no headers files (.h) found
what is mean? someone can help me?

2

The Arduino IDE displays this warning when a folder which does not contain a valid library is found under one of the libraries folders.

This might be result from several different things:

  • Sometimes there is a glitch in the Arduino IDE's Library Manager which causes an empty folder to be left behind after you install or update a library.
  • You may have placed a folder containing a sketch or some other non-library content in one of the libraries folders.
  • You may have attempted a manual installation of a library but added an extra subfolder. The library must be directly under the libraries folder.

Which of the above is the cause in your particular case, I can't say because I can't see your computer. The Arduino IDE provides a very helpful clue by telling you the path to the problematic folder, but you omitted that part of the warning message from your post so that's no help to me either.

The solution is to remove the problematic folder. If the folder contains nothing of value, then just delete it. If the folder contains something of value that isn't a library, then move it anywhere you like as long as it's not in a libraries folder. If the folder contains a library, then you'll need to install that library correctly.

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3

Same problem I have about 5 messages back in this forum. Tried deleting the folders - Arduino just created them again and gave same error message.

4

So, what operating system and version are you guys talking about?

5

dmjlambert

i use windows 10 home single language

6

pert...

so what must i do? do I have to delete the file that is considered important?

but i thinking about... how i get back a file .h for running my code... is that solution for my problem?

7

newbie30:
so what must i do? do I have to delete the file that is considered important?

If it's important then of course you shouldn't delete it. You should instead move it somewhere else on your computer.

newbie30:
but i thinking about... how i get back a file .h for running my code... is that solution for my problem?

That is meaningless to me. You'll need to make a better effort at making yourself understood.

8

pert:
If it's important then of course you shouldn't delete it. You should instead move it somewhere else on your computer.

That is meaningless to me. You'll need to make a better effort at making yourself understood.

can you tell me something?

9

Another meaningless question. Ask a clear question and I'll answer if I can. Otherwise, I've said all I can on the topic.

10

Sorry for a later reply, maybe someone found and answer already.

Anywho....What I have found it maybe a glitch in Arduino for me I found this after updating the version.

Try,

  1. Close Arduino Totally
    2)Look under you user profile: C:\Users[name]\Documents\Arduino
    Find the folder with the name you are getting the error,
    Here I did a cut and paste.
  2. Cut the folder and past it to a folder out side of the path C:\Users[name]\Documents\Arduino
  3. Open Arduino for me I found the message went away.

Hope This Helps.

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11

I went into the directory, and just did:

touch t.h

and recompiled and everything was fine, and uploaded everything was fine. For some reason it wants a .h file. God knows why.

12

This warning message is most often caused by people putting sketches in the libraries folder. Note that it's only a warning. You are welcome to just ignore it if you like, though it is kind of annoying. The reason for the warning is that the Arduino IDE scans all the folders under the libraries folder for libraries. So every unnecessary extra thing you put in the libraries folder makes the Arduino IDE a tiny bit slower. One sketch is not going to make a noticeable difference, but if you make a habit of putting sketches in there over a long period of time, it will be a problem.

Although you can silence the warning by putting an empty .h file in the folder, it really doesn't make sense to do that. You just end up with a confusing extra file that you'll probably not remember creating when you rediscover it in 6 months. The real solution is to simply move the non-library folder somewhere else if it contains files you have a use for, otherwise delete it.

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13

Just a quick update for Mac Users here:

  • on the mac Arduino by default installs libraries in ~/Documents/Arduino/libraries
  • iCloud often syncs Desktop and Documents
  • it can sync these to the cloud and then just leave a link behind to save space (or if you move to another machine, it waits until a file is needed before downloading)
  • this can lead to the Missing Library warnings (if the libraries folder is not downloaded).

To fix this issue on the Mac, use Finder > ~/Documents/Arduino > Right click libraries > Download now

Give it a little time to download all the files, and then this should make the warnings (related to the files not being downloaded) go away.

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