To solve the issue, please proceed as follow:
Go to the start menu > All programs > IRISpen 7 > Launch Validate Activation or C:\Program Files(x86)\IRISPen7\Bin\ActivateProduct.exe
Click on "Reactivate"
If after this, the issue still remains, you will have to
1. Uninstall the IRISpen 7 programs
2. Uninstall "Sentinel RMS Licence Manager"
3. Reinstall IRISpen 7