Unable to open the requested feature. Error code: -104 Error message: ERR_CONNECTION_FAILED

When I opened the previously .exe application packed by matlab application compiler, the following error occurred:

Unable to open the requested feature.

Check your internet connection and proxy settings in MATLAB Web preferences and then try starting the feature again.

Detailed information:

Error code: -104 Error message: ERR_CONNECTION_FAILED

The application has been running normally in an offline environment for a long time. This is the first time this error has occurred.

What does this error code mean? Under what circumstances will such an error code appear?

Answer 1

[Walter Roberson]

I find in a list of Microsoft error messages that error 104 means https://www.monkeybreadsoftware.de/xojo/winerror.shtml

Cannot request exclusive semaphores at interrupt time.

I see other references that associate the error with failure to initialize a TCP connection.

The MATLAB error message is hinting that it thinks there was an error establishing a proxy connection; see https://www.mathworks.com/help/matlab/import_export/proxy.html#mw_c7fdb2f3-4e14-489c-a1d4-dea2e902a1fe for more on proxy settings.

I suspect that more generally the error message might plausibly be generated if your Windows firewall is blocking the exe from establishing connections to the same host. There are some things that MATLAB uses a separate process for, including

• documentation brower (but that would not be available in an exe)
• MuPAD computation (but Symbolic Toolbox cannot be compiled)
• talking to Simscape (I believe some of that can be compiled)
• talking to Simulink (you cannot compile a simulink model using MATLAB Compiler, but plausibly you might be able to compile a function that used sim() to invoke a simulink model... I am not sure)
• Parallel Computing Toolbox

The above list of reasons MATLAB needs to talk to processes that it started is not exhaustive.

[Steven Chen]

Thanks a lot for your answer! But I’m pretty sure that the toolkit you mentioned is not used in the program. This is really a weird question. :)

[Walter Roberson]

The list I gave is not complete; there are other cases where MATLAB needs to create a process and talk to it.

Please check your Windows Firewall setting to ensure that the executable is authorized to create TCP connections.

[Steven Chen]

I have checked the code and I’m sure that my application doesn't have any operations that require networking or TCP connection. Before this error occured, the application has already been running more than one year in the same environment properly.

[Walter Roberson]

Do you have the executable on a system that is completely firewalled off from Microsoft?

If not, then you almost certainly have had Windows Updates forced upon your system: MS Windows is quite agressive about forcing updates after 6 weeks. And Windows Updates can change firewall settings, and change proxy settings. And sometimes Windows Updates just randomly 💩on fully working systems, seemingly just because they can.

Anyhow, I recommend that you contact Mathworks Support. I have never built an executable on Windows (or maybe just once.)

[Steven Chen]

Thank you very much for your help.

What’s more surprising is that this problem disappeared after the computer restarted and never happened again.😂I have already contacted supporters and we are now trying to find how this problem happened.

Thank you again for your answer！