I had this problem once on release 15.2 I believe it has been fixed in 15.7Originally posted in cdnusers.org by CTMusetti
In my case I had pin pairs defined in the differential pair coming in from the schematic with no pin use defined and on resistors and capacitors which also were defined in the wrong class "IC" apparently this confused the program. The work around was to change the class from IC to Dsicrete and then the DPTOL would calculate correctly.
this is what R&D had to say about it:
"The code does a bad match here, matching (R6.1:C9.1 with U41.5:C13.1)
and (R15.1:C13.1 with U41.6:C9.1). The code has trouble separating short
path nets with unspecified pinuses. Since the R* and C* are unspec and
not discrete types, the pins are classified BI and can be both driver
and receiver. Normally the code could separate thse, but in this case
the pins are so close together that it is difficult to separate the sheep
from the goats.
Hope this helps