Boot Scan and Full Scans stall and do not complete

[SpareTime]

New user of Avast 5.0.396, replacing Norton.
Quick Scan works fine.
First Full Scan found a virus and removed it, but never completed.
Subsequent Full and Boot Scans run consistently to about 90+%, in 45+ minutes, scanning about 63500+ files, then simply stall.  File name, byte count, completed file count don't change; run time increases and Speed (bytes/second) decrease.  Would stay that way for hours if I let it. Tried this 5 times now.

I see what might be related or similar posts, but for those I've checked, dialog always seems to stop before a solution is posted.

Clues anyone?

[igor]

Please go into the settings of the Full system scan - and on the "Report file" page, enable creation of the report file - and let all possible items (even "OK items" and "Skipped items") be included in the report. Then, run the scan again.
The resulting report will be rather huge - but when it stops again, it should be possible to say (according to the end of the report) where the problem is.

[SpareTime]

Only got 2 reports from 5 scans, possibly because I stopped other scans manually.  Hundreds (thousands?) of skipped files, and last entry on both logs is for the same skipped file.

[igor]

So, you already enabled logging of "OK items" before? There should also be many of them in the report...