First of all, this was the first day we were able to play for 4 hours without the servers crashing.
The Infected are still pushing players' characters into corners where the player can't swing at them and some will push the player character out of a building.
Invite Infected into house and let him/her trap you between furniture and wall.
This is a known issue, a limitation of the player controller/physics. Will be addressed in future updates.
Hello DesertRat and thank you for the report.
This is an issue we are aware of and it has been scheduled for a fix.
Regards,
Geez