Without admin password you are not able to start or stop engine from your PLC controller computer. Without admin password you will be denied for accessing the "User Management" console. There is no way to reset this password. So if you forget this password then you have no way to accomplish those task. But, don't worry. Always, there is a hope. Just find out the software configuration file or database. To locate that database just go to the "Setup" option. Here you will find it. Then open that database file by using any database management software like "Microsoft Access". I am here talking about "IGSS 32 (Version - 2") software. So this is very old version. Now the version -12 is available. In that case, to open that database please use "Microsoft access 2000 or Microsoft access 2003 or Office XP version". If you use Microsoft Access 2003 or Office XP version then one database conversion message will appear after opening that database. Just select the convert option. After opening that, there is a one column name "User". Simply double click the user column. Then you will be find the user list as well as password. Here the password is encrypted format. So it is difficult to retrieve the existing password. But it is so easy to reset that password. Just remove the password from that password field.
That's all. You are ready to go now. Open the user management console. Use your username and leave the blank the password field. Now the user management console should be open. I have worked on version -2 IGSS32. I am not sure about other version.
Thank You.