It could be a different issue... But it seems like you tried to change users without logging off, or trying to change something that only an administrator can and you weren't logged in as one.
It means that the user who logged on before you has higher priority than you on that computer. It might caused by a running application too. Some applications do not allow to change the user unless it finished all operations.
You can become a network administrator by creating your account and ticking that you will be the network administrator and that you are allowed access to everything.
A Symantec NetBackup 5230 is a storage website. The website creates a backup of your computer and stores it for you. This way, if your computer ever crashes, you can go to the website and restore everything to before the crash happened.
Check World Wide Learn. They have a good online program for network certification. Computer Training Schools has everything you need for computer training and network certification.
An electronic infection on a computer is known as a virus. A virus is a program that infects your computer and basically screws everything up.
Nowadays almost everything can be connected to computer network starting from PDAs, PCS, laptops and ending printers, scanners, phones, security cameras and so on.
computer network
The components and guidelines in making a good computer network tutorial are the definitions of computer network tutorial, the basics of computer network tutorial and the other guidelines and specifics of computer network tutorials.
The firewall on a computer is not, generally, a physical thing at all, but is a software program that watches everything happening on the network and stops network activity that it believes could be harmful. The firewall, as it watches what is happening on the network, could be said to be connected to the network plug, which is a small, square plug, generally on the back of the computer. It looks like an oversized phone jack. Do not plug a phone jack into a network connector; it will destroy your network hardware.
Related about computer network model
Intergalactic Computer Network
nufnet as a computer network