# A System.Net.WebException: Error: TrustFailure error occurs
**URL:** https://forum.duplicati.com/t/a-system-net-webexception-error-trustfailure-error-occurs/13389
**Category:** Uncategorized
**Created:** [November 12, 2021, 7:44am UTC](https://forum.duplicati.com/t/a-system-net-webexception-error-trustfailure-error-occurs/13389 "2021-11-12T07:44:00Z")
**Posts on this page:** 20
**Page:** 1
### Author:  [@rmsehfdoal](https://forum.duplicati.com/u/rmsehfdoal)
#### Post date: [November 12, 2021, 7:44am UTC](https://forum.duplicati.com/t/a-system-net-webexception-error-trustfailure-error-occurs/13389/1 "2021-11-12T07:44:00Z")
Hello A System.Net.WebException: Error: TrustFailure error occurs
The operating system is Centos 6
The error contents are as follows
System.Net.WebException: Error: TrustFailure (Authentication failed, see inner exception.) —\> System.Security.Authentication.AuthenticationException: Authentication failed, see inner exception. —\> Mono.Btls.MonoBtlsException: Ssl error:1000007d:SSL routines:OPENSSL\_internal:CERTIFICATE\_VERIFY\_FAILED
at /builddir/build/BUILD/mono-6.12.0.90/external/boringssl/ssl/handshake\_client.c:1132
at Mono.Btls.MonoBtlsContext.ProcessHandshake () [0x00048] in \<2f8f8f21cd414d84b3ddeb4281c7a63f\>:0
at Mono.Net.Security.MobileAuthenticatedStream.ProcessHandshake (Mono.Net.Security.AsyncOperationStatus status, System.Boolean renegotiate) [0x000da] in \<2f8f8f21cd414d84b3ddeb4281c7a63f\>:0
at (wrapper remoting-invoke-with-check) Mono.Net.Security.MobileAuthenticatedStream.ProcessHandshake(Mono.Net.Security.AsyncOperationStatus,bool)
at Mono.Net.Security.AsyncHandshakeRequest.Run (Mono.Net.Security.AsyncOperationStatus status) [0x00006] in \<2f8f8f21cd414d84b3ddeb4281c7a63f\>:0
at Mono.Net.Security.AsyncProtocolRequest.ProcessOperation (System.Threading.CancellationToken cancellationToken) [0x000fc] in \<2f8f8f21cd414d84b3ddeb4281c7a63f\>:0
— End of inner exception stack trace —
at Mono.Net.Security.MobileAuthenticatedStream.ProcessAuthentication (System.Boolean runSynchronously, Mono.Net.Security.MonoSslAuthenticationOptions options, System.Threading.CancellationToken cancellationToken) [0x00262] in \<2f8f8f21cd414d84b3ddeb4281c7a63f\>:0
at Mono.Net.Security.MonoTlsStream.CreateStream (System.Net.WebConnectionTunnel tunnel, System.Threading.CancellationToken cancellationToken) [0x0016a] in \<2f8f8f21cd414d84b3ddeb4281c7a63f\>:0
at System.Net.WebConnection.CreateStream (System.Net.WebOperation operation, System.Boolean reused, System.Threading.CancellationToken cancellationToken) [0x001ba] in \<2f8f8f21cd414d84b3ddeb4281c7a63f\>:0
— End of inner exception stack trace —
at System.Net.WebConnection.CreateStream (System.Net.WebOperation operation, System.Boolean reused, System.Threading.CancellationToken cancellationToken) [0x0021a] in \<2f8f8f21cd414d84b3ddeb4281c7a63f\>:0
at System.Net.WebConnection.InitConnection (System.Net.WebOperation operation, System.Threading.CancellationToken cancellationToken) [0x00141] in \<2f8f8f21cd414d84b3ddeb4281c7a63f\>:0
at System.Net.WebOperation.Run () [0x0009a] in \<2f8f8f21cd414d84b3ddeb4281c7a63f\>:0
at System.Net.WebCompletionSource`1[T].WaitForCompletion () [0x00094] in <2f8f8f21cd414d84b3ddeb4281c7a63f>:0 at System.Net.HttpWebRequest.RunWithTimeoutWorker[T] (System.Threading.Tasks.Task`1[TResult] workerTask, System.Int32 timeout, System.Action abort, System.Func`1[TResult] aborted, System.Threading.CancellationTokenSource cts) [0x000f8] in \<2f8f8f21cd414d84b3ddeb4281c7a63f\>:0
at System.Net.HttpWebRequest.GetResponse () [0x00016] in \<2f8f8f21cd414d84b3ddeb4281c7a63f\>:0
at System.Net.WebClient.GetWebResponse (System.Net.WebRequest request) [0x00000] in \<2f8f8f21cd414d84b3ddeb4281c7a63f\>:0
at System.Net.WebClient.DownloadBits (System.Net.WebRequest request, System.IO.Stream writeStream) [0x000e6] in \<2f8f8f21cd414d84b3ddeb4281c7a63f\>:0
at System.Net.WebClient.DownloadFile (System.Uri address, System.String fileName) [0x00088] in \<2f8f8f21cd414d84b3ddeb4281c7a63f\>:0
at System.Net.WebClient.DownloadFile (System.String address, System.String fileName) [0x00008] in \<2f8f8f21cd414d84b3ddeb4281c7a63f\>:0
at (wrapper remoting-invoke-with-check) System.Net.WebClient.DownloadFile(string,string)
at Duplicati.Library.AutoUpdater.UpdaterManager.CheckForUpdate (Duplicati.Library.AutoUpdater.ReleaseType channel) [0x000ee] in \<8d4cb1693e00483189d3952c3f0ed20f\>:0
Any solution? thank you
---
### Author:  [@drwtsn32](https://forum.duplicati.com/u/drwtsn32)
#### Post date: [November 15, 2021, 5:30am UTC](https://forum.duplicati.com/t/a-system-net-webexception-error-trustfailure-error-occurs/13389/2 "2021-11-15T05:30:08Z")
What back end are you using?
---
### Author:  [@rmsehfdoal](https://forum.duplicati.com/u/rmsehfdoal)
#### Post date: [November 15, 2021, 8:06am UTC](https://forum.duplicati.com/t/a-system-net-webexception-error-trustfailure-error-occurs/13389/3 "2021-11-15T08:06:20Z")
> [@drwtsn32](#):
>
> back end
How do I check the back end?(\_\_)
---
### Author:  [@drwtsn32](https://forum.duplicati.com/u/drwtsn32)
#### Post date: [November 15, 2021, 3:42pm UTC](https://forum.duplicati.com/t/a-system-net-webexception-error-trustfailure-error-occurs/13389/4 "2021-11-15T15:42:08Z")
It’s on the “destination” section of your backup configuration. (Where are you saving your backup data?)
---
### Author:  [@rmsehfdoal](https://forum.duplicati.com/u/rmsehfdoal)
#### Post date: [November 16, 2021, 8:33am UTC](https://forum.duplicati.com/t/a-system-net-webexception-error-trustfailure-error-occurs/13389/5 "2021-11-16T08:33:06Z")
I’m saving it to google drive. Saved to team drive.
The same symptom occurs even if you add a new backup setting to another Google account.
---
### Author:  [@drwtsn32](https://forum.duplicati.com/u/drwtsn32)
#### Post date: [November 16, 2021, 1:00pm UTC](https://forum.duplicati.com/t/a-system-net-webexception-error-trustfailure-error-occurs/13389/6 "2021-11-16T13:00:59Z")
What version of Duplicati is installed? What version of mono?
```
$ mono --version
```
I’m guessing either mono is out of date, or your trusted root certificate store (ca-certificates) is out of date.
---
### Author:  [@rmsehfdoal](https://forum.duplicati.com/u/rmsehfdoal)
#### Post date: [November 17, 2021, 1:29am UTC](https://forum.duplicati.com/t/a-system-net-webexception-error-trustfailure-error-occurs/13389/7 "2021-11-17T01:29:55Z")
Duplicati version is 2.0.6.3 beta and MonoVersion is : 6.12.0.90 .
The OS is Centos6, is there any way to update the trusted root certificate store (ca-certificates)?
Thank you.
---
### Author:  [@drwtsn32](https://forum.duplicati.com/u/drwtsn32)
#### Post date: [November 17, 2021, 3:09am UTC](https://forum.duplicati.com/t/a-system-net-webexception-error-trustfailure-error-occurs/13389/8 "2021-11-17T03:09:11Z")
I’m not sure, but to see if we are on the right track, please try setting this option on page 2 of your backup:
Save your backup config and try to run a backup again. If it works then I think we are on the right track.
---
### Author:  [@rmsehfdoal](https://forum.duplicati.com/u/rmsehfdoal)
#### Post date: [November 17, 2021, 4:34am UTC](https://forum.duplicati.com/t/a-system-net-webexception-error-trustfailure-error-occurs/13389/9 "2021-11-17T04:34:29Z")
I clicked the Test Connection button but nothing happens
Add advanced option: What hash value should I enter in Accept-any-ssl-certificate?
What value should I enter?
thank you
---
### Author:  [@drwtsn32](https://forum.duplicati.com/u/drwtsn32)
#### Post date: [November 17, 2021, 6:16am UTC](https://forum.duplicati.com/t/a-system-net-webexception-error-trustfailure-error-occurs/13389/10 "2021-11-17T06:16:51Z")
> [@rmsehfdoal](#):
>
> What hash value should I enter in Accept-any-ssl-certificate?
No hash value is required for that option, because it tells Duplicati to accept ANY certificate.
What happens if you save the config and try to run a backup?
---
### Author:  [@rmsehfdoal](https://forum.duplicati.com/u/rmsehfdoal)
#### Post date: [November 17, 2021, 7:06am UTC](https://forum.duplicati.com/t/a-system-net-webexception-error-trustfailure-error-occurs/13389/11 "2021-11-17T07:06:37Z")
When I save the settings and run a backup, nothing happens.
The log occurs as shown in the picture
Saving the settings is normal.
However, there is no response when running the backup.
Thank you
---
### Author:  [@drwtsn32](https://forum.duplicati.com/u/drwtsn32)
#### Post date: [November 17, 2021, 1:41pm UTC](https://forum.duplicati.com/t/a-system-net-webexception-error-trustfailure-error-occurs/13389/12 "2021-11-17T13:41:57Z")
I see a “connection timed out” error now, which sounds like Duplicati can’t reach your backup destination.
---
### Author:  [@rmsehfdoal](https://forum.duplicati.com/u/rmsehfdoal)
#### Post date: [November 18, 2021, 2:08am UTC](https://forum.duplicati.com/t/a-system-net-webexception-error-trustfailure-error-occurs/13389/13 "2021-11-18T02:08:35Z")
How to solve it? thank you
---
### Author:  [@drwtsn32](https://forum.duplicati.com/u/drwtsn32)
#### Post date: [November 18, 2021, 1:03pm UTC](https://forum.duplicati.com/t/a-system-net-webexception-error-trustfailure-error-occurs/13389/14 "2021-11-18T13:03:14Z")
Do some basic network tests from the machine that is running duplicati:
```
nslookup duplicati-oauth-handler.appspot.com
ping duplicati-oauth-handler.appspot.com
telnet duplicati-oauth-handler.appspot.com 443
```
nslookup should return IP address, ping should give you replies, and telnet should connect (not give you a connection timeout error).
---
### Author:  [@rmsehfdoal](https://forum.duplicati.com/u/rmsehfdoal)
#### Post date: [November 18, 2021, 1:40pm UTC](https://forum.duplicati.com/t/a-system-net-webexception-error-trustfailure-error-occurs/13389/15 "2021-11-18T13:40:50Z")
ping communicates well as in the picture
Authentication token error occurs even when the Accept-any-ssl-certificate option is enabled
---
### Author:  [@drwtsn32](https://forum.duplicati.com/u/drwtsn32)
#### Post date: [November 18, 2021, 1:44pm UTC](https://forum.duplicati.com/t/a-system-net-webexception-error-trustfailure-error-occurs/13389/16 "2021-11-18T13:44:15Z")
> [@rmsehfdoal](#):
>
> Authentication token error occurs even when the Accept-any-ssl-certificate option is enabled
Yes because now you have a different problem from your first post. The problem now is that the connection to that destination doesn’t appear to work. What happened with that third command (telnet)? It looks like you may not have pressed enter.
---
### Author:  [@rmsehfdoal](https://forum.duplicati.com/u/rmsehfdoal)
#### Post date: [November 18, 2021, 1:56pm UTC](https://forum.duplicati.com/t/a-system-net-webexception-error-trustfailure-error-occurs/13389/17 "2021-11-18T13:56:54Z")
When I type telnet [duplicati-oauth-handler.appspot.com](http://duplicati-oauth-handler.appspot.com) 443 I get a blank screen as shown in the picture
---
### Author:  [@drwtsn32](https://forum.duplicati.com/u/drwtsn32)
#### Post date: [November 18, 2021, 5:20pm UTC](https://forum.duplicati.com/t/a-system-net-webexception-error-trustfailure-error-occurs/13389/18 "2021-11-18T17:20:40Z")
That’s good, that means a basic connection test succeeded. Not sure why you are getting a connection timeout when you try to run a backup though.
---
### Author:  [@rmsehfdoal](https://forum.duplicati.com/u/rmsehfdoal)
#### Post date: [December 8, 2021, 8:34am UTC](https://forum.duplicati.com/t/a-system-net-webexception-error-trustfailure-error-occurs/13389/19 "2021-12-08T08:34:13Z")
Any other solution? Still getting authentication failure, referencing inner exception error.
Is it a certificate issue?
---
### Author:  [@drwtsn32](https://forum.duplicati.com/u/drwtsn32)
#### Post date: [December 8, 2021, 3:51pm UTC](https://forum.duplicati.com/t/a-system-net-webexception-error-trustfailure-error-occurs/13389/20 "2021-12-08T15:51:10Z")
The first error you posted sounds like a certificate issue. But the second one was a connection timeout issue.
What error are you still getting?
If you are getting the certificate error, then please see my earlier post about setting the “accept any ssl certification” option as a test.
[Next page](https://forum.duplicati.com/t/a-system-net-webexception-error-trustfailure-error-occurs/13389.md?page=2)