Just spent about 2 weeks with Microsoft support on a problem related to one way trust and using the peoplepicker-searchadforests for Sharepoint. You can find out more about the property here: http://technet.microsoft.com/en-us/library/cc263460.aspx
The problem in our situation was that we previously had set the property to be able to search the forest which in our case was called contoso.local. SharePoint was not returning users from the trusted domain in people picker but what was more confusing was that people picker would return users from the trusted domain who had been previously added. So initially, we couldn’t diagnose that it wasn’t returning all users but thought it was only having a problem with a few users. In the end, we found the problem to be that contoso.local was no longer being recognized as a forest but rather just as a domain.
Why was it being now recognized as a domain and not a forest anymore? No clue. If you have any ideas please chime in because that is still a mystery to me. I’ve tripple checked and our forest is still the same name. I did notice this issue happened after the April cumulative update although I’m not sure it is related.
So our property value for peoplepicker-searchadforest had to change from:
stsadm -o setproperty -url http://contoso.com -pn peoplepicker-searchadforests -pv “forest:contoso.local“,contoso\account,*****;”domain:contoso.local”,contoso\account,****
to the correct value:
stsadm -o setproperty -url http://contoso.com -pn peoplepicker-searchadforests -pv “domain:contoso.local“,contoso\account,*****;”domain:contoso.local”,contoso\account,***
It took us 2 support technicians and an escalation then finally after 2 weeks the issue was fixed with Microsoft support. We spent a lot of time making test sites with multiple configurations but had completely missed this one detail of trying domain instead of forest. Hope this saves someone else some time!