MobaXterm gets stuck on "Please wait while opening file..." dialog

Question

I am using MobaXterm v20.6 build 4532 to connect to a Linux machine over SSH. I am trying to open a file in the Scp panel on the left by double-clicking on it, and this brings up a dialog box saying "Please wait while opening file...", and it gets stuck here forever.

Interestingly enough, this works on some servers but not others. Is there some way to debug this? Is there a log file which shows the scp command that MobaXterm is trying to run?

Answer 1

I figured out the problem. I was able to enable logging by running "MobaXterm.exe -log". This left a log in C:\Users\jdoe\Documents\MobaXterm\MobaXterm.log. This was printed when I tried to open a file:

[11:31.39.305]  (SSH-Browser)    Starting MobaSCP(2, OpenFile, /local/jdoe/.bashrc, C:\Users\JDOE\DOCUME~1\MobaXterm\slash\RemoteFiles\526608_2_0\.bashrc)
[11:31.39.307]  BEGIN ShellExecuteA(C:\Users\JDOE\DOCUME~1\MobaXterm\slash\bin\MobaSCPOpenFile.exe, -v -batch -scp -load "TERM5266082" mobauser@mobaserver:"/local/jdoe/.bashrc" "C:\Users\JDOE\DOCUME~1\MobaXterm\slash\RemoteFiles\526608_2_0\.bashrc")
[11:31.39.308]      ShellExecuteA: ShellExecuteEx succeeded.
[11:31.39.308]  END ShellExecuteA(C:\Users\JDOE\DOCUME~1\MobaXterm\slash\bin\MobaSCPOpenFile.exe, -v -batch -scp -load "TERM5266082" mobauser@mobaserver:"/local/jdoe/.bashrc" "C:\Users\JDOE\DOCUME~1\MobaXterm\slash\RemoteFiles\526608_2_0\.bashrc")
[11:31.39.405]  [MobaSCP2]  Multiplex=0
[11:31.39.406]  [MobaSCP2]  HOSTNAME: 192.168.1.104
[11:31.39.406]  [MobaSCP2]  USERNAME: jdoe
[11:31.39.724]  Received verification request for hostkey: ssh-ed25519@22:192.168.1.104
[11:31.39.724]  Hostkey corresponds to the cached one
[11:31.39.748]  WMNewTab2: Saving sshkey and NOT CONNECTING SSH-Browser...
[11:31.39.748]  BEGIN SavePassword
[11:31.39.749]  END SavePassword
[11:31.39.845]  [MobaSCP2]  Using SCP1
[11:31.39.845]  [MobaSCP2]  Connected to 192.168.1.104
[11:31.39.845]  [MobaSCP2]  Protocol error: Expected control record

Looks like the "Expected control record" error was being caused by my .bashrc printing output. Apparently this confuses SCP: https://documentation.help/PuTTY/faq-pscp-protocol.html

I was able to fix this by changing my .bashrc to not print anything.