Software Deployment

I ran into a bit of a snag with a Business Object rollout this week. In cases where an initial install gets interrupted on a machine, all subsequent silent installs fail and I find the following in the install log:

Detected in-progress transaction, but not running in resume mode.
MessageDialog title:   Incomplete Operation Detected
MessageDialog message: Installer has detected that a previous operation did not complete.  Do you want to resume?

in a normal (non-silent) install you get a nice dialog asking if you want to resume the other setup, however, a silent install fails on this.

Setup is being executed using -q -r <full path to ini file> parameters

Does anyone know either a command line parameter to trigger resume mode on silent installs if needed, or a way to 'clean up' the failed install on the target machine that allows a regular install to run?

Thanks in advance for any feedback

PJ