Your workflow is unique 👨‍💻 -  tell us how you use Dropbox here.

Forum Discussion

Niko K.'s avatar
Niko K.
New member | Level 1
10 years ago

Sync API framework not connecting to Dropbox server?

Hi,

I’m using the Dropbox Sync API framework in my Mac app and I have had one user report problems enabling the Dropbox sync in my app.
The framework never connects to the Dropbox sync, but keeps on trying with this log:

23/03/2015 23:10:17.952 [WARNING] status: SSL: DBHTTPRequest.mm:535: Unknown authentication method NSURLAuthenticationMethodServerTrust for Dropbox host: api0.dropbox.com
23/03/2015 23:10:18.548 [WARNING] status: SSL: DBHTTPRequest.mm:535: Unknown authentication method NSURLAuthenticationMethodServerTrust for Dropbox host: api1.dropbox.com
23/03/2015 23:10:20.936 [WARNING] status: SSL: DBHTTPRequest.mm:535: Unknown authentication method NSURLAuthenticationMethodServerTrust for Dropbox host: api0.dropbox.com
23/03/2015 23:10:23.444 [WARNING] status: SSL: DBHTTPRequest.mm:535: Unknown authentication method NSURLAuthenticationMethodServerTrust for Dropbox host: api0.dropbox.com
23/03/2015 23:10:25.257 [WARNING] status: SSL: DBHTTPRequest.mm:535: Unknown authentication method NSURLAuthenticationMethodServerTrust for Dropbox host: api2.dropbox.com
23/03/2015 23:10:25.576 [WARNING] status: SSL: DBHTTPRequest.mm:535: Unknown authentication method NSURLAuthenticationMethodServerTrust for Dropbox host: api0.dropbox.com
23/03/2015 23:10:26.035 [WARNING] status: SSL: DBHTTPRequest.mm:535: Unknown authentication method NSURLAuthenticationMethodServerTrust for Dropbox host: api1.dropbox.com
23/03/2015 23:10:26.796 [WARNING] status: SSL: DBHTTPRequest.mm:535: Unknown authentication method NSURLAuthenticationMethodServerTrust for Dropbox host: api0.dropbox.com
23/03/2015 23:10:27.879 [WARNING] status: SSL: DBHTTPRequest.mm:535: Unknown authentication method NSURLAuthenticationMethodServerTrust for Dropbox host: api0.dropbox.com
23/03/2015 23:10:29.526 [WARNING] status: SSL: DBHTTPRequest.mm:535: Unknown authentication method NSURLAuthenticationMethodServerTrust for Dropbox host: api0.dropbox.com
23/03/2015 23:10:31.913 [WARNING] status: SSL: DBHTTPRequest.mm:535: Unknown authentication method NSURLAuthenticationMethodServerTrust for Dropbox host: api0.dropbox.com
23/03/2015 23:10:31.994 [WARNING] status: SSL: DBHTTPRequest.mm:535: Unknown authentication method NSURLAuthenticationMethodServerTrust for Dropbox host: api1.dropbox.com
23/03/2015 23:10:34.361 [WARNING] status: SSL: DBHTTPRequest.mm:535: Unknown authentication method NSURLAuthenticationMethodServerTrust for Dropbox host: api0.dropbox.com
23/03/2015 23:10:37.420 [WARNING] status: SSL: DBHTTPRequest.mm:535: Unknown authentication method NSURLAuthenticationMethodServerTrust for Dropbox host: api0.dropbox.com
23/03/2015 23:10:47.851 [WARNING] status: SSL: DBHTTPRequest.mm:535: Unknown authentication method NSURLAuthenticationMethodServerTrust for Dropbox host: api0.dropbox.com
23/03/2015 23:10:48.298 [WARNING] status: SSL: DBHTTPRequest.mm:535: Unknown authentication method NSURLAuthenticationMethodServerTrust for Dropbox host: api0.dropbox.com
23/03/2015 23:10:50.748 [WARNING] status: SSL: DBHTTPRequest.mm:535: Unknown authentication method NSURLAuthenticationMethodServerTrust for Dropbox host: api0.dropbox.com
23/03/2015 23:11:08.228 [WARNING] status: SSL: DBHTTPRequest.mm:535: Unknown authentication method NSURLAuthenticationMethodServerTrust for Dropbox host: api0.dropbox.com
23/03/2015 23:11:21.033 [WARNING] status: SSL: DBHTTPRequest.mm:535: Unknown authentication method NSURLAuthenticationMethodServerTrust for Dropbox host: api0.dropbox.com
23/03/2015 23:11:23.451 [WARNING] status: SSL: DBHTTPRequest.mm:535: Unknown authentication method NSURLAuthenticationMethodServerTrust for Dropbox host: api0.dropbox.com
...

I’m unable to reproduce this myself. Other than that I didn’t have any complaints regarding the Dropbox sync in my app and it works fine on my test devices.

Do you have an hints what the log message could mean?

Thanks a bunch,
Niko

API

7 Replies

Replies have been turned off for this discussion
  • Stephen M.40's avatar
    Stephen M.40
    New member | Level 1
    10 years ago

    I just started getting this as well, has anyone been able to resolve this?

  • Steve M.'s avatar
    Steve M.
    Icon for Dropbox Staff rankDropbox Staff
    10 years ago

    Sorry for the delay! In the future, I'd recommend posting API questions in this forum, where responses are generally much faster.

    My guess would be something about the networking set up for this particular user. Do you have any details about their environment? Perhaps they have an unusual set of trusted certs or they're going through an HTTPS proxy (and thus the cert doesn't match) or something like that. I expect it's going to be very hard to debug without a setup to reproduce the issue. :-(

  • Brendan D.'s avatar
    Brendan D.
    Explorer | Level 4
    10 years ago

    I'm having the same issue now with a customer of mine using the Sync API.

    5/31/15 8:14:01.042 AM Tap Forms[5788]: [WARNING] status: SSL: DBHTTPRequest.mm:535: Unknown authentication method NSURLAuthenticationMethodServerTrust for Dropbox host: api0.dropbox.com
    5/31/15 8:14:01.068 AM Tap Forms[5788]: [WARNING] status: SSL: DBHTTPRequest.mm:535: Unknown authentication method NSURLAuthenticationMethodServerTrust for Dropbox host: api1.dropbox.com
    5/31/15 8:14:01.441 AM Tap Forms[5788]: [WARNING] status: SSL: DBHTTPRequest.mm:535: Unknown authentication method NSURLAuthenticationMethodServerTrust for Dropbox host: api0.dropbox.com
    5/31/15 8:14:01.896 AM Tap Forms[5788]: [WARNING] status: SSL: DBHTTPRequest.mm:535: Unknown authentication method NSURLAuthenticationMethodServerTrust for Dropbox host: api0.dropbox.com
    5/31/15 8:14:02.714 AM Tap Forms[5788]: [WARNING] status: SSL: DBHTTPRequest.mm:535: Unknown authentication method NSURLAuthenticationMethodServerTrust for Dropbox host: api0.dropbox.com

    and it goes on and on. I'll ask them to check their certificates to see if there are any expired ones.

  • Brendan D.'s avatar
    Brendan D.
    Explorer | Level 4
    10 years ago

    So did this ever get resolved? I'm having the same issue now with a bunch of customers.

  • Steve M.'s avatar
    Steve M.
    Icon for Dropbox Staff rankDropbox Staff
    10 years ago

    Did you ever learn anything from the first customer about their network setup?

    Among the other customers who are seeing this issue, is there any commonality in their network setup? (Perhaps they all work at the same company, for example?) We haven't heard a lot of reports of this, so I assume it's not a widespread issue. Narrowing down what these customers have in common will be key to figuring out what's going on, so please let us know what you find out.

  • Brendan D.'s avatar
    Brendan D.
    Explorer | Level 4
    10 years ago

    Unfortunately I haven't figured out from anyone who has this problem what the issue might be. Some have it on one Mac but not the other in the same office. I asked them to check their Keychain for expired certificates and proxy server configurations, but none had them. So I'm very puzzled by this. I've never seen it myself.

About Dropbox API Support & Feedback

Node avatar for Dropbox API Support & Feedback
Find help with the Dropbox API from other developers.

The Dropbox Community team is active from Monday to Friday. We try to respond to you as soon as we can, usually within 2 hours.

If you need more help you can view your support options (expected response time for an email or ticket is 24 hours), or contact us on X, Facebook or Instagram.

For more info on available support options for your Dropbox plan, see this article.

If you found the answer to your question in this Community thread, please 'like' the post to say thanks and to let us know it was useful!