The cause of this delay is that in our network, @user.home points to some directory on a server that is sometimes very busy. So at startup this directory is hard to reach and this causes the delay.
Note that the special syntax @user.home will simply be replaced by the Java System property user.home. (See  for more information on the OSGi locations and the special syntax you can use in the config.ini file.) I assume you are on a Windows system? Here, the JVM has a rather strange way to initialize the user.home property: It is defined as the parent folder of the Desktop Shell Folder (See  for more details. This is actually a long standing JVM Bug -- and it seems to be finally resolved with Java 8!)
Are you sure that the Desktop Shell Folder correctly points to a network location? Doesn't this slow down your setup in general?
So is there an alternative for this in a way that I still have different directories for the different users. For example, if this directory would always be on the local PC it would work fast.
There is a special syntax to refer to environment variables in the config.ini file. (See section "Variable substitution in config.ini" in .)
So you could use something like the following (assuming that the environment variable USERPROFILE points to a reasonable location in your setup ):