what is Instafinda - it keeps coming up as a virus when I run Avast but I cant delete

[lixylix]

it now matter how I try - any tips on this please?

Possibly it's Instafinder, or a variant. It is some kind of Browser Help Object, which installs itself in Internet Explorer (are you using that browser?). Insterfinder - CA Sercurity Advisor
InstaFinder - Wikipedia

Try removing by using Spybot Search & Destroy