To improve the security of this external trust, security identifier (SID) filtering is enabled. However, if users have been ...

To improve the security of this external trust, security identifier (SID) 
filtering is enabled. However, if users have been migrated to the trusted 
domain and their SID histories have been preserved, you may choose to turn 
off this feature. 

For more information about SID filtering and how to turn it off, see the help
for netdom trust /FilterSids or see Help and Support.