Eddy
3
What file was deleted ?
Check the virus chest and/or the log file(s)
There is no need to buy anything.
If the files/folders are recoverable with software this will do it for free > http://www.cgsecurity.org/wiki/TestDisk
avast is correct (up to a point).
You install software at your own risk.
But the main question perhaps is…
Where is your backup ?