The Ms-Pl is incompatible with many free software licenses, as it imposes a unique restriction:
(D) If you distribute any portion of the software in source code form, you may do so
only under this license by including a complete copy of this license with your distribution. [...]
Many OSI-approved copyleft licenses require that linking or interacting code must be licensed in a manner that does not further restrict user rights. This conflicts with the Ms-Pl, as it specifically prohibits the right to re-license.
There are many GPL, LGPL, and AGPL-licensed libraries - yet we are forced to choose between using them - and using this library. We are also prevented from using any copyleft license in consuming software.