Strange behaviour with eicar.com test file

I had tested some things with eicar.com file, but I had strange behaviour.

1/ I tried to download eicar.com
2/ I had the amon warning message. Disinfect button was greyed (why ?), and delete or rename did not work (why ?), only solution was to "ignore". But isnt it dangerous to do this ? What ignore does ? Can an ignored file damage the computer ?
3/ Then, I download eicar.com again. As it was ignored, I had no warning message anymore.
4/ So, result I have on my download folder an infected file that will not be detected anymore, so can damage my computer (eicar.com is not dangerous, but an other virus could be)
5/ I sent the message to myself.
6/ When I receive the message, pop3 system warned me I received an infected file. In fact it didnt really say it was a virus, but as it was amon pop3 system I supected so
7/ Only choice then was to close the window. No way to disinfect it.

Anyone can comment on this ? As I would be sure I am well protected. And imagine if my wife is using my computer. She has an amon warning message, she click on all windows to close amon, so the only working window is ignore one, so she click on it and close amon with an infected file on the computer, without knowing what she does

Oh... Moreover amon told me this file will be ignored until next reboot of my computer... but I nearly never reboot my computer

Thanks