I was using Mathematica 11.1 under Windows 10, 64 bit. Yesterday morning I had a Windows 10 update and during the morning my virus scanner AVG warned me that one of the Windows files was corrupted with the virus
Win32/Herz.b. Very likely a false alarm, but I did not take any risk and allowed AVG to protect me.
Yesterday and today I did quite a lot with the Workbench and Mathematica 11.0. I do not remember if I have used Mathematica 11.1 as well, but anyway, since this afternoon in Mathematica 11.1 the frontend works nicely, but the kernel fails.
For example, when I try to evaluate
1+1, in the upper left corner I see Mathematica running, the cell bracket is dark, and then everything stops: the message that it is running disappears, the cell bracket becomes normal, but no
Out-labels and no output.
When I use
LinkSnooper and evaluate
LinkSnooper starts up as usual, but almost immediately a window pops up showing "Wolfram Kernel for Windows does not work any more."
Of course I am not sure that this behaviour has something to do with the AVG protection. But anyway, following the advice on the AVG website I used the RemovalTool for completely removing AVG, reinstalled AVG and moreover reinstalled Mathematica 11.1. That did not help, the symptoms still are the same.
Fortunately, the problem is restricted to Mathematica 11.1. I can use Mathematica 10.4 and 11.0 normally.
Have other people had similar experiences? What can I do more than reinstalling Mathematica? All help to get Mathematica 11.1 running again is highly appreciated.
As I wrote, I was doing quite a lot with the Workbench and Mathematica 11.0. I just found that one of my attempts seems to have lead to an automatic loading of a context. At the moment I have no idea how I can get rid of this autoloading. I had a look at the
Global Options, found one place where that context turned up and removed it. I forgot what option it was. It did not help, when I restart Mathematica, the context is still loaded. But to my surprise, now the Mathematica 11.1 kernel runs again! Nice that it works again, but nevertheless unsatisfactory, because of both the reason and the solution for the loss of a kernel seem have to do with the Workbench.
The application that I was playing with has in the
PacletInfo.m file explicitely version Mathematica 11.0. What might have happened is that when Mathematica 11.1 started up, due to an incorrect
Global Option setting it despite the restriction loaded the application and thereby tried to use some
LibraryFunctions that silently crash the kernel, see here.