Addon DLL's not added to FSX.CFG

[Soulflight 97]

Hi there,after I renewed my FSX.cfg because of some other problems which are gone now, my FSX stopped adding the dll's needed for some addons (mostly planes) automatically to the "trusted" section. The popup you normally get, which asks whether you want to add this file to the trusted list, simply does not appear and most complex planes get loaded with lots auf gauges or in some cases (CLS 747) with the entire VC missing.I am running win7 64bit and FSX with administrator rights.any ideas about this really strange problem?thanks in advance....

[Soulflight 97]

To specify my problem: is there any option, setting or configuration that can prevent FSX from showing the digital Signature Dialog that appears when selecting an addon plane for the first time?