Solution: avrdude stk500_getsync(): not in sync resp=0x30 error for Arduino

So the reader is aware: This article covers the main causes for this issue, but some of the other Instructable users have found somewhat "niche" causes to the issue that were not covered in this article and are discussed in the comment section below. If this article does not solve your problem, please visit the comment section below.

I have had this error: I would plug my Arduino Uno into my Windows 7 PC (this guide should be relevant for Windows 8, Vista and XP also) but whenever I would upload any sketch to the board, all I would get is

avrdude stk500_getsync() not in sync resp=0x30

for a response. This board however worked seamlessly with my Linux machine.

After much searching online, I found there was no 'clear' solution to this.

Joyfully, the fix is actually very easy (at least for me, hopefully for you as well!). So far, there seems to be 2 big causes to this issue: you have the wrong COM port selected (the IDE does not see your board) and/or your Arduino drivers are not set properly.

Unlikely Cause: Bootloader is missing

Before we begin, we should check the bootloader of the Arduino for comprehension. If the bootloader is gone or corrupt, this can cause the issue.

To do this: power and reset the board. Check to see if the pin 13 built-in LED lights; if it is not then your bootloader may be missing. If this is the case, then your problem is beyond the scope of this guide. I would suggest visiting this Sparkfun guide:

If the LED lights, then your bootloader still exists.

Cause #1: Wrong COM Port 

With the Arduino plugged to the computer, open "Device Manager" and check the "Ports". Check to see if an Arduino device is listed here; if it is, then make note of which COM port the Arduino is on and check that you have this selected in the Arduino IDE (Tools -> Serial Ports). If the COM port your board is on does not show within the IDE, then try different USB ports.

If you can't even see "Ports"; then for some reason, your computer isn't even recognizing that a device is plugged into it. Test your computer by plugging other USB devices into that port. Possibly your Arduino fails at life; try it with other computers.

Cause #2: Drivers not Installed

This is what you should see when you open Device Manager:

If you don't see an Arduino device listed under Ports; then you are probably seeing an "Unknown Device". Check to make sure that "Unknown Device" is indeed, the Arduino by plugging and unplugging the board from the computer. "Unknown Device" should appear and reappear. Assuming this is the case, you will need to install the drivers manually for your Arduino. Windows XP, Vista and 7 users may continue with the guide; if you are a Windows8 user, then please make reference to the comment left by finnigan16 below.

Right click on that "Unknown Device" and select "Properties". Click on the "Driver" Tab. Below, you can see I already have the driver set, hence why my window reads "Arduino UNO R3 (COM4) Properties", when yours will probably read "Unknown Device Properties".

Select to "Update Driver..." and then choose to select the folder containing the driver on your computer. Conveniently, you already have the drivers for the Arduino on your computer when you downloaded the Arduino IDE. Navigate to the Arduino folder you downloaded that contains the Arduino IDE.  In that folder, go to the "drivers" folder and choose the "drivers" folder itself (see the picture below for the path). The computer should automatically choose to install one of the drivers within the folder you selected. Simply proceed with the installation and that should fix the problem.

Make sure the Serial Port is then selected correctly!

If you have checked the possible causes discussed here and your issue still isn't solved, be sure to check the comment section. Some of you have found niche causes to the issues which are discussed below.
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finnigan161 year ago
great Instructable. Unfortunately It didn't work for me, however I did find a fix so I thought I'd post it here for anybody else with the same problem. My problem is that I'm using Windows 8 and apparently the arduino drivers aren't signed and therefore windows 8 will not utilize them. Fortunately YouTube user beachedwhale found an easy work around that'll get it working without turning off driver signing. You can watch his video by following this link:

In a nutshell, you update the driver through device manager and use the wizard to pick from a list of device drivers on your computer, when this list comes up you choose a Compaq Ricochet Wireless USB Modem, apparently the two devices use the same driver, you just need to change a few of the driver's settings once it's installed (make sure the baud rate is 9600, etc...).

It only takes about two minutes to do, definitely worth a try if your getting this error and running Windows 8.
N.fletch (author)  finnigan161 year ago
I never verified this error with Windows8; thanks for helping make my Instructable more comprehensive. I'll make an edit above pointing to this for those with Windows8.

hey guys, I have an ARDUINO PRO MINI and i don't know what driver to install for it, i don't think there is a specific driver for it, or is there? Help please! :(

N.fletch (author)  PeppaQuotaPeepsyesterday

When you downloaded/installed the Arduino IDE, the driver should be included in the drivers folder. When updating the driver, you only need to select the "Drivers" folder and let Windows pick the driver. At least that's how I did it.

creative_3514 days ago

I removed the power(5v) of blue tooth and it worked for me

the same here.

if the bluetooth is connected unplug the 5v.



Thank you very much!!

It was a simple fix for me. COM1 was automatically selected in Ardunio Tools and I had to set it to COM3.

Thank you for the help!!

chearn4271 month ago

Worked for me; great instructable!

ecozcelik1 month ago

Thank you so much !!!

tvance9294 months ago

My problem ... I had a wire coming out of pin 0 -- Dont do that when uploading... ugh!

"DISCONNECT ANY WIRES going to pin 0 (RX) while you do the upload." <-- thanks Keith!

@tvance929 - thank you! That was my problem, too.

You saved me a lot of pain! I don't know what changed, I tested out my system, a greenhouse control, then placed it in the greenhouse. It failed, a wire disconnected. I brought it back in, and had this problem. Fortunately, I came across your suggestion quickly. I adjusted my outputs to begin at 1 rather than 0, and poof, problem solved! So a wire in output 0 seems to generate the problem intermittently.

@tvance929 You were the guy for my problem ! Thank you for sharing your fix. I indeed did connect my pin 0 to the Tx of a device i want to control from my arduino and ended up with this error (resp=0x07 in my case).

The funny thing is that i even didn't need to connect this pin since i'm not expecting any data from my device, just have to tell it what to do.

Thanks to Keith too :)

ceeyus1 month ago

Help Please...

I am using a Freeduino board with atmega 8 and i am having this error. I tried installing drivers multiple times , restarted it , tried changing the com ports and even the board (arduino uno to arduino duimilanov) but no avail . only thing i can see is a green light and also there are no issues with the boot loader.

Dave J8 months ago
Thank you for this instructable, I just spent an hour trying to get this sorted out and your instructions got my sketch up and running in 10 minutes.
N.fletch (author)  Dave J8 months ago
Thanks! Glad to hear this guide is still helping people.

It IS still helping people... And the niche comments too... This article & comments helped tremendously.

vairamani6 months ago

user should select the right comport by verifying it in the device manager and choose the correct comport in tools->serialport

This was *exactly* my fix. Device Mangler, etc; all checked out fine... but until I set the COM port to match in IDE (Arduino 1.0.5) just had a blink on the onboard LED... which added to the irony / frustration, since I was starting with "Blink" as my first sketch. Thanks ton Vairamani, you nailed it!! Now... on to bigger projects! ;-)

Joe_M1 month ago

The problem for me was with the lack of experience, I was selecting Upload with programmer, where by simply using Upload was successful.

squiresfan3 months ago

You legend. Worked a treat for me. Wheeeee look at my LED go..... Blinking LED today... take over the world tpmorrow :)

davisbr94 months ago


I have the Due ("ATMega3X8E" on the chip), and I seem to be getting this error regardless of what I try.

I have verified the COMM port, many times. Changed them, even.

I have tried both of the Due boards available in the IDE list. Many others as well.

I have uninstalled and reinstalled, updated, etc. the drivers for the board.

I have changed USB cables multiple times.

I have tried on two completely different Due boards, each from completely different vendors.

Nothing works. It's not the bootloader, my "L" LED comes on normally. The only difference between the two Due boards is the one I have today, the "L" LED blinks when powered. The previous one stays on.

There is nothing on the main forums about this issue, other than what this write-up says.

Has anyone else fixed this issue, specifically on the Due? Thanks!

summitboarder5 months ago

To try and make this an even more comprehensive solution guide to the given error, I found removing any wire attached to pin 0 (RX) from the arduino made the error go away.

Raitis5 months ago

Thank you so much! Can barely believe that the reason for my frustration while looking for an error in code or circuit was solely my dumbness with not checking IDE. :D

N.fletch (author)  Raitis5 months ago

Glad it helped! Usually when I get stumped, I start over with very basics: "if I can't upload this code and it seems fine, can I upload any code at all?". Then I build back up from there.

edbarted7 months ago

In case of displaying a notice: "avrdude: stk500_getsync(): not in sync: resp=0x00"
download the CDM driver for particular operation system from: .
After the installation a new port (com) will be created.
To set Arduino to a new com port and the problem is solved.

Elminator8 months ago
Thank you! My arduino uno was giving me trouble and I didn't know how to fix it. Your instructions helped me get some of the basic projects off the ground.
jvlutters8 months ago
thank you bro this did really help me :D
klug10 months ago
If you have this problem with an avr barebones only arduino tick Show verbose output during upload and you will see what's the issue. Most likely your uart bridge fails to reset your chip while uploading. (problem with the 100nF cap/ resistor or connection)
If you have an arduino board maybe you blew the chip or the ftdi chip if not driver/ide is the issue.
playinmyblues11 months ago
Great short tutorial! It was just what I needed to get my Arduino running on Windows.
N.fletch (author)  playinmyblues11 months ago
Great! Glad to hear it has helped you out!
Solved my problem...thanks for sharing the solution...cheers!
mahadevan1 year ago
I have also had this problem and circumvented using pressing the 'reset' button Arduino at the point the 'avrdude' is trying to flash. More info is at my blog 
tzq33tdq1 year ago
My Arduino Uno R3 did this and your Instructables helped me fix it! Thanks mate, you're a life-saver!!!
chriscos1 year ago
You will also get this error if you have he wrong board selected from Tools > Board.

I have multiple arduino's. If I forget to change from Arduino Uno to Arduino Duemilanove (AT Mega 328). Then I get this error if I try to upload to my Duemilanove board.
Ardu-kes1 year ago
response to my self. Removed the switch that was connected to Uno pin1(TX) and the board worked fine again. :-§ The switch was switched/disconnected/connected at different points, so that was another layer of confusion.
Ardu-kes1 year ago
Got the same error, suddenly.
IDE updated to 1.0.3.
Changed Uno R3 to a different one. Upload works, but COM6 changed to COM3.
Swapped in original Uno, 'COM3 not available. Select COM port'. Selecting COM6.
Same error appears.
Uninstalled COM6 in dev man. PC XP reboot.
Dev man:COM1 and COM2. Plugd in orig Uno. New HW found.
Install driver, already in system. Finish. New HW on COM6 (dev man)
Start Ardu IDE 1.0.3, load Example->Basic->Blink - Upload - OK.
Load own sketch, connect LCD, upload ok.
So, the COM-port initial selection is stored in the UNO?
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