Now it works thanks to “libc6:i386”
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Hallo Alyana
I wanted to know WHY the “:” and “-” are so important so I searched (with google) and found an explanation, which I’ve pasted in below.
WHATS THE DIFFERENCE BETWEEN libc6:i386 AND libc6-i386?
libc6:i386 is the i386 version of libc for i386 architecture kernels/systems. This is for running packages built for i386 systems and would be required if you are trying to use i386 packages on an amd64 system. This is called multiarch.
libc6-i386 is the 32bit development package of libc for amd64 systems. This is not for running software, its for compiling and linking 32 bit code.
source::
posted::
19.05.2016
-%-%-%-%-%-%-%-%-%-%-%-%-%-%-%-%-%-%-%-%-%-%-%-%-%-%-%-
So I installed the missing library, exactly as you suggested.
Of note is that “apt” added a message to its output saying that the following 2 packages were “suggested” for installation as well:
- glib-doc:i386
- locales:i386
I did not install these.
I used Synaptic to uninstall “clamav” and “clamTk”.
I then opened caja with sudo via the terminal, located the installer file using caja, set the permissions, and double-clicked it. After that everything went just as it should.
Thank you for contacting the company and providing this information for the rest of us. 
Of interest, is that Dr. Web (a Russian maker of anti-virus software) says clearly in its handbook that the library is required for its product. However, just like the ESET documentation you quoted they talk of the “-” version. Looking at the explanation of the difference above I wonder if the people writing the “Handbooks” actually know the difference and its importance.
@Wimpy
Would it be worth including “libc6:i386” in the basic install of Ubuntu-Mate?
A happy new year to you all. 