ipython notebook not displaying output cells

[guesser198414]

ipython notebook version 0.13, using the latest Google Chrome 2012

The problem is similar to this one:
http://comments.gmane.org/gmane.comp.python.ipython.user/9032

[ivanov]

this was on a windows 7 machine, qtconsole for that kernel worked fine, execution ran only for the first kernel (starting another notebook would not run anything in that notebook and just stall on In[*].

[ivanov]

@guesser198414 I forget, did we try disabling all of the windows firewalls and any other firewall that might have been running?

[guesser198414]

No, we didn't. I tried to turn off all the firewalls a couple of weeks ago but the IPython Notebook still did have outputs. But there might be multi-firewalls with different security levels at our lab, and I suspect I might not completely turn off ALL of them.

Anyhow, IPython Notebook had been working for a while (maybe a couple of weeks) since the installation this Aug and none of my colleagues has problems on IPython Notebook.

[ivanov]

Just ran into this issue again at the UC Berkeley Software Carpentry bootcamp today. For this person it is on Chrome 21.

[douglatornell]

We ran into this issue today at the UW Software Carpentry boot camp. Win 7, Anaconda CE, Chrome 25.
Problem was resolved by allowing 127.0.0.1 through Sophos firewall as described in http://stackoverflow.com/a/13075334/371740

[ivanov]

apparently, sometimes, even this is not enough. Had the same issue today at the UCB Pythoon Bootcamp: Win8 with Sophos. adding 127.0.0.1 exception and rebooting did not work. Neither did following the

In the option Block access to malicious websites select off. After that reboot, doesn't work without rebooting!

directions from #3311

[RafaelCosman]

Just ran into this on Windows 7 with Chrome. Python is Anaconda version 1.8.2, and IPython is version 1.0.0. Tried disabling firewall, didn't work.

[ivanov]

Hi @RafaelCosman, we've been trying to get to the bottom of this issue, and there are a few possible ways of trying to fix it. They are documented here, could you try them and report back?

[jdfreder]

@leewhite you need to mute the thread, there should be a "Mute Thread" button at the bottom of the page.

[lornearnold]

Allowing 127.0.0.1 through Sophos firewall worked for me.
Thanks @douglatornell

[nwin]

The last comment in the stackoverflow thread made the trick ipython notebook --ip=localhost works. Would it be a solution to use localhost by default ore are there other problems arising from that?

[Carreau]

@nwin notebook listen (at least) on localhost by default already (default on u'' which get translated to localhost in here, just slightly more involve than "just" localhost for some reason.

Only difference will by I guess that explicitely specifying localhost might have IPython do less sheningan to try to get local interfaces, and maybe it is all this scanning that is triggering Sophos to block us.

[nwin]

@Carreau probably you are right about this. ipython notebook --ip=127.0.0.1 works too. Just ipython notebook doesn't work.

[astrofrog]

I've had this issue with my students and --ip=localhost seems to do the trick.

[nwin]

I don't think this issue is solved. Sophos also blocks the access when I run ipython on another computer.

[rossant]

What do you mean @nwin ? FWIW this trick works perfectly on all my Windows computers with Sophos.

[nwin]

I can't use this trick if I want to access the notebooks from another computer. If I start python notebook --ip=* on one computer, the notebooks don't work on another computer if the latter one runs Windows+Sophos.

[minrk]

@nwin if a firewall is blocking connections between computers, then it is probably behaving correctly. If you want access across a network, you may have to tell your firewall explicitly that the notebook should be allowed.

[nwin]

@minrk No, it’s not some firewall. It is the Sophos virus scanner. This time running on the client computer only. It apparently uses some kind of misbehaving detection scheme to determine whether a connection is harmful or not.

And as you can see, this issue can be fixed on the iPython side by starting up differently. But I don't know TCP/IP well enough to see what the exact difference between the normal startup and --ip=localhost/--ip=127.0.0.1 is and if that can be further exploited to never trigger this “web intelligence service”.

The point is, going to a colleague and saying “Let me show me the calculation I made – wait, may I first disable this virus scanner service?” is not very convincing.

[aparente]

This is happening with my computer on the Stanford network, but only sometimes. Bash commands (cd, pwd) work fine, but most times I try to run python code it either spits out an error (if the code is broken) or if the code "works" (will run if I run it directly in ipython or write a python script) it does nothing at all and highlights the next code box below it. It was working just fine until yesterday when I re-encrypted my computer with the Stanford BigFix software (includes sophos). Occasionally pandas code will work, but sometimes it won't. Its very confusing.

Running it by specifying either the ip or localhost as described does not work either.

p.s. @ivanov I was in your software carpentry bootcamp at stanford :)

[cacbic]

I had the same issue, ran anaconda prompt as administrator(right click run as admin..) and then everything works fine.

[takluyver]

We do not recommend running the notebook as administrator. It may work around some problem you're experiencing, but it increases the impact of any security holes.

[kavyaprasad]

Restarting the kernel helped me!