Check
HyperCOM3 english manual (pdf)
Bootneck : you setup AExplorer with "hyperCOM3.device" in tooltype of AE icon ? Attention : case sensitivity, hypercom3.device won't works !
Please, give us versions of your hyperXXXX.device (hyperCOM3 and hyperPAR.device in DEVS:) and your vmcresource.library (in LIBS:).
Edit : added extras linkshttp://www.vmc.de/swr/hypercom298.lha (drivers)
In case of problem, you could try to contact
http://www.vmc.de/eng_all.html