This is most likely to be caused by a lack of physical memory in the machine and therefore not enough memory to start the application.
One work-around is to instruct Schemus to request less memory on startup. The most convenient way of doing this is to place parameter requesting a smaller amount of memory in a file within the folder containing Schemus.
You can download an example below (Schemus.exe.vmoptions), which requests 1024M of memory. This figure can be edited to request less, for example 512M if 1024M is still too much. Note that if you synchronise a large number of addresses, making this number too small could cause Schemus to run out of memory, which would cause synchronizations to fail. On a Windows system, assuming the application was installed to the default location, this file should be copied to C:\Program Files\Schemus where Schemus.exe should be located.
If you also need to adjust the amount of memory for the command-line Schemus, you should make another copy of this file and name it schemusc.vmoptions.
Alternatively, on a Windows system, you can invoke Schemus from a batch file (see schemustest.bat below) which controls the amount of memory used.

	Schemus.exe.vmoptions
	schemustest.bat