Re: Enabling "DCOM Callback"

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Thanks, I might take a look at the MSDN sample at some point.

Unfortunately my COM+ application has now stopped working completely in the
client=NT to server=XP direction. I can't get simple
single-class-single-method COM+ apps to work in that direction now - the
server object class is not creatable on the client.
I had a try at the MSDN VB6 DCOM client/server testing sample, to see
whether I could remove COM+ from the equation, but it uses the "Package and
Deployment Wizard", and so doesnt work, being unable to find a number of
files while generating the installers.
I found the MSDN 'AtlDraw' C++ DCOM VS2005 sample but unfortunately the
release build had compile errors and the debug build required a missing debug
mfc dll on the NT client machine (understandably). Perhaps more effort in
that area would result in success.

Use of Ethereal (packet sniffer) does indicate that the client is
communicating with the server using the 'DCERPC' protocol, although I dont
know what is going on apart from being able to observe a failed 'remote query
interface' for what is (google) interface IClassFactoryEx, then a release of
what looks like it might be an IClassFactory pointer. I can't see where the
IClassFactory is 'got', and can't see any attempt to create an instance of my
server object from this class factory. Basically all I really get from this
is that the client is able to connect to the server, at least.

I've tried to switch off everything security related that I can find,
although there is no indication that it is a security problem (then again,
there's never much indication of anything useful when it comes to DCOM
problems!):

On the NT client:
DCOM enabled.
Default Authentication Level: Connect
Default Impersonation Level: Identify
Default security:
Everyone
...
Default Launch permissions:
Everyone
...

On the XP server:
DCOM Enabled
Default Authentication Level: Connect
Default Impersonation Level: Identify
Access Permissions:
Limits: Everyone (everything checked)
Default: Everyone (everything checked)
Launch/Activation Permissions:
Limits: Everyone (everything checked)
Default: Everyone (everything checked)

The COM+ Application Security:
'Enforce access checks' UNCHECKED
Authentication level: Packet
Impersonation level: Impersonate






"Alexander Nickolov" wrote:

I haven't used it myself I admit. You can contact the author.
Also, you can look at the DCOMPERM sample (by the same
author) on MSDN.
.

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