AVG Anti-virus keeps telling me that I have a threat in the file
C:\WINDOWS\cdsnp1.dll. AVG can’t quarantine or delete it – it says that it
cannot access to the file. If I try, it tells me something about the file being
in use. What do I do?
This is likely one of the many manifestations of a very common problem. No,
not the virus – I honestly have no idea what that is. I mean the inability of a
program, or even you, to delete a file because it’s in use.
In some cases Windows prevents you from deleting files because they’re in
use by some program running on your machine – often Windows itself. Deleting it
while in use by a running program could crash your machine, or worse.
So what if you know you need to delete a file, but it’s in use from the
very moment you boot your system, and no matter what software you shut down
it’s still “in use”?
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Windows also provides the ability to perform actions when it boots – before
any programs are running. How this is specified is fairly obscure, and not
something you want to deal with directly (it’s buried in the registry, if
you’re really curious). Fortunately, there’s a free utility to do it for
When run, MoveOnBoot asks you to specify a file:
In this case I’ve selected the file c:\t\pagra.txt.
Hit next, and you’ll get a choice:
may become unbootable …”
It’s called MoveOnBoot because the most common, and perhaps
safest action is not to delete the file, but rather rename it or move it to a
different folder so that the program that eventually tries to load it won’t
find it. However, you can also instead make a copy of the file, or truly delete
the file, if you so choose.
In my case, I’ll select “Move”, and then it asks:
I’ve left the location the same (c:\t), but simply changed the name of the
Finally, MoveOnBoot confirms what it’s about to do:
Even though it says “Start”, it simply schedules the action to occur the
next time you reboot.
Now, when you reboot your machine, once it comes back up, the file specified
will be renamed, (or deleted or copied, depending on what you specified) before
any other program has an opportunity to place it “in use”.
CAUTION: you can really hurt your system using
this utility. Do not delete any Windows system files or your system
may become unbootable and you’ll need to reinstall Windows from your
Use this utility with care.