IVssBackupComponents VTable problems
(too old to reply)
2017-11-05 08:24:35 UTC
Hello All,

I'm trying to use the Volume Shadowcopy Service in Windows XPsp3,
specifically the VSSAPI.DLL, and am running into a problem: I cannot seem to
find the correct VTable for the IVssBackupComponents interface. :-(

In my case I'm trying to call the StartSnapshotSet method (which has a
single argument), only to see after it returns that the stackpointer
indicates much more has been popped off the stack (enough for 7 extra
arguments). This leads me to believe that I'm pointing to the wrong VTable
entry, which in turn means I have the wrong VTable altogether.

The problem is, I've taken that table pretty-much directly from an MS SDK

Who has the VTable for the IVssBackupComponents interface (and related ones)
for me ?

Rudy Wieser
2017-11-06 10:13:56 UTC
As it turns out, the VSSAPI.DLL which comes with the installation seems to
be a quite different beast than the one the SDK is talking about.

I did disassemble the VSSAPI.DLL my OS had far enough to find the
VssBackupComponents vtable and the methods it refers to. And as luck would
have it, each method contained its name for execption throwing purposes.
Funny that, two of the methods showed "Bacup" (missing the "k").

Alas, when looking for one of the methods (RemountReadWrite) I had to
discover no info for it (and thus probably neither rfor the whole thing) was
available (anymore?) ...

In short: Case closed.

Rudy Wieser