Does it have videotron FW loaded or DLinks OEM firmware? If videotron, thats probably the reason. There is a good post on the DLink forum about putting DLink OEM firmware on a 825 thats got videotron FW loaded. If your using OEM firmware,
What Hardware version is your router? Look at sticker under router.
What Firmware version is currently loaded? Found on routers web page under status.
What wireless modes are you using? Under Setup/Wireless/Manual.
Try single mode G or mixed G and N on 2.4Ghz and single mode N on 5Ghz?
Channel Width set for Auto 20/40Mhz or try 20Mhz only.
What security mode are you using? Preferred security is WPA-Personal. WPA2/AES Only. Some WiFi adapters don't support AES, so you might want to try TPIK only or Auto.
What wireless devices do you have connected?
Any cordless house phones?
Any other WiFi routers in the area? Use »
www.metageek.net to find out.
Turn off Short GI, WLAN Partition and Extra Wireless Protection if you have it. Under Advanced/Advanced Wireless.
The DIR-825 IS a great router if set up correctly.