1) reconfigure.exe - see if it's available

2) ptcstatus.bat
in C/Program Files/PTC/licenses - status

3) Check if firewall on the machine is blocking that port
control panel->firewall ->advanced settings 35:00

4) License server not starting with windows
In Flex Net -> Status should be Up
If it's not running, Start FlexNet Admin Service isn't set to run on startup
lmadmin and ptc_d.exe should run as a service when you startup computer, right click and GO TO SERVICE
Task Manager -> Services -> lmadmin_ptc
Right click and Open Services
Startup Type should be Automatic

5) Vendor Daemon is down - this is usually caused by importing a license file when the license server is NOT down

Uninstall FlexNet, delete the lm_admin service in the CMD prompt, then reinstall it