Windows NT scanning Problems

HI!

I Am very pleased with the new version 5!

But there is one thing I cant get right. When I scan for an Windows NT workstation, I almost always get these errors:

FAILURE : One of the WMI components is not registered properly.

Please report the problem to the system administrator, with the Error Code - 1.133.504.222.281.

or:

FAILURE : General failure while performing the operation

but in some workstations, there is no problem with scanning.

its the same language on the workstations and same servicepacks

SP 6 NT 4.0

So I compared the services, and started a few. Still nothing happened.

So what am I doing wrong??
Please help