Yealink T23P PC Port Issue

[Mohamed123]

Dear,

We user Yealink T22P since 3 years without any issue, we updated all our phones
to Yealink T23P (About 150 Phone), all new phone working well, except PC Port issue as below

1) We use Vlan ID: 21 for voice
2) We use Vlan ID: 27 For Data ( PC Port )
3) I configured all phones normally as before, but PC port not working at all, when i connect any PC to Yealink T23P PC Port, the pc can't obtain IP Address, i searched Yealink Forums and tried to apply every solution without success, the strange thing is any PC with windows 8 working well, but PCs with windows 7 or PCs with Linux can't.

Kindly i need a solution.