Had a different router everything was working fine, until i replaced my router to a dlink dsl 2640u , wireless router. i can open all sites but sites beginning with https cant be opened. it says web page unavailable. tried everthing but helpless. gmail,, bank accounts,,,,etc cant be opened.

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You may need to have your computer checked as well from a computer technician because its your computer that is always asking for the network key and not the router. Once you reset your router to default settings and make use of the routers default wireless configuration, it will always stay that way. There might be a possibility that the wireless card on your computer is the one that is having a problem because it always loses the saved wireless settings from your D-Link Modem Router.

Does your PC work on other networks reliably? If so- it's likely the DLink failing. The firmware issue is just a symptom as well. I'd recommend either seeing if you could use your DSL provider's original modem (if this was a replacement) or if you have another router- if it doesn't drop at that point, it was definitely the router/modem. However, if it drops still, you may have a line issue- but I severely doubt this since the symptoms are pointing to the DLink.

I’m happy to help further over the phone at https://www.6ya.com/expert/susan_42b401e0b1603d8a

There a great article at General Router Setup.
If you need more help post back!
Thumbs and testimonial are welcome!

Here is a direct link to show you how to secure your router, now you will need to reset your router to default settings before securing to do that press and hold the reset button located on the back of the router for 15 seconds or until router resets, you may need a paper clip to access the reset button.
http://ftp.dlink.ru/pub/ADSL/DSL-2640U/Description/DSL-2640U_B2_Manual.pdf

all wireless devices must be allowed in the router by either MAC address or by name. This is accomplished by logging into to the router and setting up the device in with the wireless setup feature in your router. The router will not allow the device to connect without permissions.

disable the firewall and antivirus in your system and check it

Thank you

Hello there!

Only thing that can cause your wlan light not working consistantly or with some blinks (which is normal thing) is bad lan cable which leads from your ADSL modem to your wlan entrance on your wireless router, please check that cable in order to fix that problem. Cable doesnt need to be coaxial so it can have 2 different lan sets (2 poles of exits male and female exit). Thats it ! =)

Please rate solution! =)

Sincerely
Aleksandar Adzic

i have a dlink dsl2640u when i go in 192.168.1.1 and try to turn on the wireless and save it reboots 3 to 4 times then it stays on but the wireless is off any help

Have you tried turning DHCP on?