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I downloaded Avast using terminal command wget and the download and installation was successful.
Then I chose check updates(database) from the interface. As soon as the updates were downloaded the following problem started.

An error occurred in avast! engine: Invalid argument

What should I do to correct the problem?

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This is a known problem in Avast. You need to increase the maximum amount of shared memory allowed.

  • To load it without rebooting sudo sysctl -w kernel.shmmax=128000000
  • To make it permanent, edit the file /etc/sysctl.conf (gksudo gedit /etc/sysctl.conf), and add this line to the end of the file kernel.shmmax = 128000000
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thank you. I used the first option and I have managed to get it to work. the second option, i don't know how to carry it out. what should i do to carry it out? – Sizwamulena Kabila Oct 3 '12 at 21:54
There, I changed the program nano to gedit, so you can edit graphically. – Sepero Oct 3 '12 at 22:29
This didn't work for me but using 256... worked instead. – pbhj Jun 11 '14 at 0:12

I use Puppy Linux Slacko and this solution worked for me.

I've a 4GB memory. So this solution, I guess will work for computers with higher memory not low ones.


SHMMAX=`sysctl -n kernel.shmmax`
[ $SHMMAX -lt 128000000 ] && sysctl -w kernel.shmmax=128000000

in /usr/lib/avast4workstation/bin/

Then Open terminal and type

sysctl -w kernel.shmmax=200000000

Hit Enter.

And then start avast. Now Avast works!

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