Or it could be a simple configuration problems the below tips will help in some instances to fix some problems that you might be experiencing.
If it a laptop make sure you havent knocked the wireless switch on the laptop which turns the wireless on & off.
Make sure you have the right password in your WEP, WPA or WPA2 key.
Make sure cables are correctly inserted and that they are not damaged.
Make sure you have the correct and compatible drivers installed for the wireless adapter.
Make sure you have no missing drivers.
Check the Network connection settings to see if they are set correctly.
The below commands can be run in Windows and can help to reset the internet and any faulty settings.
1/ Open up CMD prompt
2/ Make sure you run CMD prompt as Administrator else these will not work properly..
3/ Type netsh int ip reset reset.txt and press enter
4/ Type netsh winsock reset and press enter
5/ Type netsh advfirewall reset and press enter
After this restart your computer.
This will reset the winsock , firewall and adapters and take them back to the default settings that Windows originally came with.
This doesnt always work there may be a large amount of damage done to the computer and you may need to take it into a technician.
Hope these hints help.
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