I recently opened an .xls (Excel) file from an Upwork job opening and received an email from them that they believed my computer was infected by a virus as a result. I have downloaded and run Avast - done a full system scan. Avast found 1 infection in my trash but can't delete it for some reason. Any help would be greatly appreciated.
I am using a Macbook Pro running OS X - Yosemite, 10.10.5