Scry Location and Teleport (or other spells)

[Shin Okada]

A DM can prevent scry and teleport tactics in various way. A villain may be using nondetection, or may just have high enough will save. Or, always moving, invisible, in dark places and such.

But how a DM can prevent PCs from using Scry Location (Complete Scoundrel) and Teleport to an enemy's secret base or the capital of a secret kingdom, once the name of the place is known?