There was an error syncing to garmin Connect

This has been the case for me for over 4 months now. No amount of uninstall/reinstall Garmin Express clears it and the watch has been through multiple software updates and a factory reset during this time. However, despite getting that message the sync has always actually happened, so in reality the functionality is not impaired from my experience of this. A bug that needs fixing in due course? Yes. A bug that actually stops me using any aspect of the watch? No.

It does NOT sync activities for me, and it is very annoying! It used to work during firmware 4.10, but then intermittently while on 5.xx, and then no longer worked. For at least 6 weeks now is not working anymore.

Your situation is different to other reports. I assume you've already tried uninstalling Garmin Express (completely, including app data), then reinstalling. If you can, see if the watch will sync on another machine with Garmin Express installed; if there's a problem with the Garmin Express app on the first machine, this test will identify if that is the case. Assuming both machines with Garmin Express fail to sync, the first thing to try on the watch side is safely copy your activities to somewhere (from the GARMIN/ACTIVITIES folder) then delete the contents of the activities folder. That might clear a corrupted activity file that won't sync. You can similarly try the same with courses if that doesn't work. Beyond that you could try a factory reset of the watch; understanding that this is a pain as you really need to start from scratch afterwards as any element of backup and restore might just put a corrupt file back on the watch. Beyond all of that, I suspect your best bet is to contact Garmin Customer support in your country.

I did all you have suggested (except trying with a different PC, but guess what? I don't have another PC/Laptop; should I buy one?!?), including contacting Garmin support which is just guessing about the issue, recommending same things that I did already. At one point they acknowledged that there was an issue with their servers. After that last month event, something was fixed, because many users - myself included - could not re-register the watch after resetting the watch, which they recommended. So after that, it worked once or twice and then again with this connection error! This is so lame and unprofessional! Not to mention how frustrating is paying premium for this kind of "treatment". I'll see how long I'll take on this frustration and then I'll move to another product. Not Garmin, obviously!

SOCEB Have you solved your problem? I have the same problem and I am in the process of solving the issues with Garmin support. I really unhappy that I have problems with such fundamental function as synchronization. I tried many PCs, laptops, operation systems (Win 7, 8, 10) always with firewalls turned off. I tried everything but still nothing. I have Huawei phone so no chance to sync via Bluetooth in a phone, but interesting is that nor syncing via Bluetooth on my laptop (HP Spectre x360, Win 10) is possible. I can add the device, start syncing, but then the error occurs. Every other device is working and syncing with my mobile and PC but Garmin Fenix 5 just not.... Sooo frustrating...

One of your activities (or courses) is corrupted (had the same problem). Found the solution in another forum (can't remember wich one...)

1) If you can find out wich one (e.g. by syncing them on batches to garmin web dashboard uploader), delete it from your watch.
2) After then remove your watch from Garmin Express
3) delete the device folder from your watch from your pc - found in "C:\ProgramData\Garmin\CoreService\Devices\xxx"
4) add your watch again in garmin express and sync it

thankyou, Chimcen - I had a syc error, too (on two different W10 laptops) and your solution worked for me.
Syncing activities worked via Bluetooth to my Android, charging worked, too, even the update to FW7

and now I have the Running Power fields on my F5 - today is a good day :)

One of your activities (or courses) is corrupted (had the same problem). Found the solution in another forum (can't remember wich one...)

1) If you can find out wich one (e.g. by syncing them on batches to garmin web dashboard uploader), delete it from your watch.
2) After then remove your watch from Garmin Express
3) delete the device folder from your watch from your pc - found in "C:\ProgramData\Garmin\CoreService\Devices\xxx"
4) add your watch again in garmin express and sync it

Can anyone explain in greater detail on how to do this? Thank you for helping.

wich point is not detailed enough for you?

I fix one of my activities file .FIT .. the file was not corrupt at all but the Android and my PC was not able to sync it. WHY? Any clues Garmin ??? So this is what I did below.

I hook my watch to my PC. Go to the watch thru the USB and in the "Activity" of Garmin, there are a bunch of .FIT file. Look for the date that it is missing and having your problem.

Log into Garmin connect on the website. Go to Dashboard and All the Activities and IMPORT that .FIT file. It works for me! Now I see my activity.

BUT .. when I sync on the Garmin Connect on my PC, I still get that "Sync Error" message. How do I get rid of this? Thanks!