Hi Geos...
"ASHQUICK caused an invalid page fault in module <unknown> at 0000:1b10f3dd."
It only seems to happen the first time I scan the file. If I repeat the process or immediately scan a different file it works fine.
That sounds identical to the problem I had with AshSimpl causing an invalid page fault. I had to update my Jet40 to SP7 because, according to Microsoft's description, Jet40-SP3 is buggy.
Try the trick mentioned by Vlk:
Try the following: open the file avast4.ini located in the <avast>\data folder, and replace the line
Database=ODBC
to
Database=XML
Then restart the computer and see if it helps.
If that fixes your problem (but does cause another - e.g: you can select specific folders scanning, but always get a full scan) then you will need to update

I am not to sure that you need the MDAC-TYP.exe, but take it anyway in order to "complete" the update.
Avast! uses a Jet database (is it Access 2000? - see the file ...\Avast4\Data\Avast4.mdb) and the SP3 version of Jet40
must 
be updated in order to work with it.
I think I had to change to Jet40-SP3 when I had to install the MS-XML SDK.
Hope it helps
