When this happens I know to check the router configuration as some block connections by MAC addresses. The Ethernet cable test is always done. It's only a test.
The other test I do to sniff out if it's hardware or software(drivers, config) is to boot from the handful of Live Linux OSes. I tend to stick with the top 10 from Distrowatch.com
No learning Linux is required.
[UPDATE 8/1]: I have even purchased a new adaptor (same one), I attached it to a different PCIe slot like I'd done with my old one and I am 100% sure that I have been entering the correct wireless key password...still no success, when I try to connect to the router it simply won't allow me to connect, saying "Cannot be connected". My parents' two laptops and my phone have successfully been connected to the internet while this problem has occurred.
fff:
[ORIGINAL]: I've had the wireless TL-WDN4800 adaptor for 1 year and 9 months, since I built my PC. It has usually worked perfectly and problems are generally down to my own router but in the last week or so my internet has been 'acting up' and has at random moments suddenly cut off. I learnt that this was down to the adaptor suddenly not being registered as connected so I turned the adaptor off and on again and this seemed to get back the internet. However, this continued to occur, multiple times in a single hour and today the adaptor has completely cut off.
On the taskbar it is simply grey and has a red "X" on top - when I hover over it, a message just says "TL-WDN4800 Not connected" like it did previously but turning it off and on again fails to do anything. I have looked on the internet at suggestions such as installing a new driver for the adaptor but the latest available driver was the one that I already had. I tried re-installing this but still it did not work. I did the same for the adaptor's 'connection' and the "Wireless Configuration Utility" on the disc that came with it but neither resolved. I also changed the PCI slot that it was connected to as I heard this might help but it failed to do so. ++ I don't own and I am unable to connect an ethernet cable to my PC. For now it appears that I am completely unable to access the internet. Did it die or something? Haha. If so then could you please suggest another ideal adaptor or let me know if I should purchase the same one.
Here is the adapter: http://www.amazon.co.uk/TP-LINK-TL-WDN4800-Wireless-Express-Adapter/dp/B007GMPZ0A/ref=sr_1_1?ie=UTF8&qid=1450818559&sr=8-1&keywords=tp+link+tl-wdn4800
&here is my PC build just in case: http://uk.pcpartpicker.com/user/ShiunTraze/saved/jznp99
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