Session Start Problem: "Communication channel has faulted!"

[vroosioks]

We have the same problem at one school. Some computers (Windows 11) have SEB running, others have a message "SEB failed to start new session". Computer restart doesn't help. The school installed program from https://safeexambrowser.org/download_en.html and then also manually installed the necessary programs from this page requirement section https://github.com/SafeExamBrowser/seb-win-refactoring/releases/tag/v3.6.0.

2024-03-04_12h34m29s_Client.log
2024-03-04_12h34m29s_Runtime.log

I think there's been a similar problem here, but I don't think it's worked out. #555

Originally posted by @vroosioks in #806 (reply in thread)

[vroosioks]

The school has 2 types of computers, SEB 3.6.0 worked on Lenovo computers (picture 1) and did not work on HP computers (picture 2).
Pic 1

Pic 2

lenovo-hp-wmic.xlsx

[dbuechel]

Thanks for your report. This is indeed a known issue for which we currently don't have a solution:

2024-03-04 12:34:33.876 [01] - INFO: Initializing runtime connection...
2024-03-04 12:34:33.894 [01] - DEBUG: [RuntimeProxy] Trying to connect to endpoint 'net.pipe://localhost/safeexambrowser/runtime/4b93e454-bf92-49f4-aa16-9fba36ca2092' with authentication token 'caf42f93-6d10-49a5-89e6-9b30989298e3'...
2024-03-04 12:34:33.924 [01] - DEBUG: [RuntimeProxy] Communication channel is opening...
2024-03-04 12:34:33.950 [01] - WARNING: [RuntimeProxy] Communication channel has faulted!
2024-03-04 12:34:33.971 [01] - WARNING: [RuntimeProxy] Endpoint 'net.pipe://localhost/safeexambrowser/runtime/4b93e454-bf92-49f4-aa16-9fba36ca2092' could not be found!
2024-03-04 12:34:33.971 [01] - ERROR: Failed to connect to the runtime. Aborting startup...

Our current suspicion is an interference of either Windows (Defender) or then a third-party application like anti-virus software or alike. But we'd need a reliable way to reproduce the issue, otherwise there's nothing we can do at the moment, various attempts at determining the underlying cause have thus far failed.

[dbuechel]

I see that you have Bitdefender installed; you might want to try and disable it on the systems with the problem to verify whether it may be interfering with SEB. Or you could uninstall all software which is on the HP systems, but not on the Lenovo systems in an attempt to pin down a possible interference with SEB.

[github-actions]

This issue is stale because it has been open for 28 days with no activity. It will soon be closed automatically if there are no updates.

[frederik-it]

I hope someone will read this, because I mentioned this issue probably as first in #765
Even SEB 3.7 has the same error as I've described in previous link: SEBDummy can't be changed. I suppose the start of the problem has to do with some actions that couldn't be done even if I'm the administrator of the device, because it's also managed by Intune.
Because I read Antivirus. We're using Defender for Endpoint, the cloud solution by Microsoft. It isn't possible to turn it off...
Some devices have this problem, while many others doesn't. But SEB has to work on all devices. Hopefully SEB could fix this. Thanks!

[dbuechel]

@frederik-it This issue relates to another problem, namely the inter-process communication of SEB's application components and does not relate to the ease of access configuration issue.

With respect to the issue mentioned in #765, I can only reiterate the information already provided in comments #765 (comment) and #765 (comment): If you're not using the SEB Service application component, then SEB will not manipulate the ease of access registry value (but will validate it, which is likely the cause of your issue). Thus please try to bypass the service component in your configuration(s) and clean up any potentially remaining ease of access registry values (either manually via Registry Editor or then e.g. using the SEB Reset Utility).

[frederik-it]

Hi, thanks for the answer. I thought it was about the same issue.
Now I did some investment in some of these laptops having the problem with SEBDummy.
I've noticed after some searching that there was an underlying service installed on these devices, that acted as an antivirus. Probably it was installed with some other software. So the problem of my school has been fixed. Thank you to say in these posts to look for an antivirus or something similar. So Defender for Endpoint is working good with SEB.

[dbuechel]

@frederik-it Excellent, that is good to know and thank you for providing the information, it may help other users.

[ThomasL-AP]

I'm seem to have the same issue.

Related issues
I found those related issues, but either they are closed or seem outdated.

• SEB fails to start: Communication channel has faulted #555
• Error: Seb failed to start a new session! #225
• Seb won't open. #479
• New session problem - even at startup #765

Describe the Bug
The startup of Safe Exam Browser fails. Log files mention:

• "[RuntimeProxy] Communication channel has faulted!"
• [RuntimeProxy] Endpoint 'net.pipe://localhost/safeexambrowser/runtime/6cba798f-602e-47fd-8dc0-aabb45996dcc' could not be found!
• ERROR: Client instance terminated unexpectedly during initialization!
• ERROR: Failed to start new client instance! Aborting procedure...

Steps to Reproduce
Steps to reproduce the behavior:

1. Got to exam
2. Start SEB either with the sebs://-link or the config.seb-file
3. Seb seems to start but then fails with the usual warning to check log-files

Expected Behavior
Seb starts properly.

Screenshots

Version Information

• OS: Windows 11, 23H2 (build 22631.4602)
• SEB-Version: 3.8.0 (x64), Build 3.8.0.742

Additional Context
I disabled and ended the tasks (in task manager) of the only anti-virus, anti-malware and security software I could find: HP Wolf Security. This did not help. i might have missed something, but the computer seemed pretty new and with very few bloatware/other security software. System tray showed only one other uncommon software (AMD updater or performance software... "Adrenalin" or something)

I found a work around though:

1. Download config.seb file
2. Start a command line with admin-rights
3. Navigate to Downloads folder
4. Open the config.seb file
   This will run SEB with admin rights and make it start correctly.

Log files
First two logs of a failed startup

• 2024-12-19_11h37m16s_Client.log
• 2024-12-19_11h37m16s_Runtime.log

Then a succesful run with admin right (using the work around)

• 2024-12-19_11h38m22s_Browser.log
• 2024-12-19_11h38m22s_Client.log
• 2024-12-19_11h38m22s_Runtime.log