This issue was originally marked as duplicate of issue 170291, that is already resolved. This issue is still valid, so this seems to be another issue, but it might be related.
Build: NetBeans IDE Dev (Build 200911070201)
VM: Java HotSpot(TM) Client VM, 14.3-b01, Java(TM) SE Runtime Environment, 1.6.0_17-b04
OS: Windows XP, 5.1, x86
mkroll: Open Project Properties
Maximum slowness yet reported was 3828 ms, average is 3828
Created attachment 90864 [details]
No reports since 6.8. Likely fixed.