When I launch Mathematica and write the first command and press Return+Shift, whatever the command is, it takes forever to evaluate — about two minutes. Immediately after the first evaluation (even if I abort it) everything is back to normal.

If I then restart the kernel, the problem does not come back.

If I just wait for a couple of minutes after the start-up, the problem also does not appear.

From these observations, I would conclude that this problem is not related to the kernel (though I'm not a programmer).

I've been seeing this behavior since upgrading to 10.3 and it persists in 10.3.1.

Is this a bug? Is it Mac-only? Is it known?

  • $\begingroup$ What are the stats of you computer? RAM? processor? etc? $\endgroup$
    – rcollyer
    Commented Jan 4, 2016 at 22:32
  • $\begingroup$ @rcollyer 2 GHz Intel Core i7, 8 GB 1600 MHz DDR3, Intel HD Graphics 4000, SSD memory. Mac OS X 10.11.2 $\endgroup$ Commented Jan 4, 2016 at 22:33
  • $\begingroup$ It might be helpful to check the activity monitor (search for via spotlight) while the issue occurs to see if there is high load on the CPU or RAM $\endgroup$
    – Sascha
    Commented Jan 4, 2016 at 23:22
  • $\begingroup$ @Sascha no, almost nothing is happening — 3-4% load from Mathematica. $\endgroup$ Commented Jan 5, 2016 at 0:01
  • $\begingroup$ I have never experienced this problem on my Mac with Mathematica 10.3.1 or earlier. MacBook Pro: Processor 3 GHz Intel Core i7; Memory 16 GB 1600 MHz DDR3, 1 TB SSD; Graphics Intel Iris 1536 MB; OS X 10.11.2 $\endgroup$
    – Bob Hanlon
    Commented Jan 5, 2016 at 0:41

4 Answers 4


I got the same problem and solved it by doing this. Just go to the Preferences->Internet Connectivity and turn off Allow the Wolfram System to access the Internet, then relaunch Mathematica.

  • $\begingroup$ Thanks for this solution. Of course, with this setting WolframAlpha doesn't work. It is pretty frustrating that this bug persists in 10.4. $\endgroup$ Commented Mar 4, 2016 at 1:49

First, try resetting Mathematica by following this article:


Even if there's no reason why it should work, please try it.

If that doesn't work, then try running the Mathematica kernel:


You should be able to evaluate simple things like 2+2. Can you? If not, are there error messages? Try to evaluate:


Does that work? What is the output?

If none of this works, you may want to contact Wolfram Technical Support by email using this form:


  • $\begingroup$ Resetting didn't do anything. It does evaluate everything, but only after a couple minutes since the start-up pass (or if I start and abort the first evaluation). $\endgroup$ Commented Jan 5, 2016 at 21:45

This annoying bug has finally been fixed in 11.0


I have just solved this problem by turning off the automatic updates in the preferences. Hope it will work for you too!


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