Internet Trojan or virus removal guide


Update the firmware - Download here  Link-1          Intranet Link

List of things-to-do that will hopefully help you update it without any hassles.
0. Check your firmware version by looking at System Info on admin interface of the router.

1. Get the firmware from D-link India site or download from above link.
2.Warning: Dont update with wrong version
3. Download the .IMG file through anyone of the link provided .

4. Now, connect your laptop physically to the router using a RJ-45 network - the regular Ethernet cable.
5. Disconnect wi-fi access of the router or disable wi-fi temporarily.
6. Browse to the Admin User Interface of the router by browsing the management IP - typically and give your user name and password as "admin"
7. Go to Maintenance menu>Firmware update on the left and then click on "Browse".
8. Select the file from the Computer folder using the browse button.
9. Click on "update firmware",(dont double click) if you have pressed it correctly, you will get a message "Upgrade in progress - please wait for a minute -Will reboot automatically"
10. Don't do anything else!
11. WAIT.

12. Don't do anything - WAIT.
13. Keep waiting - if you observe your router, the buttons will flash at some point and indicate that it is restarting.
14. Subsequently, your page should refresh and the home page of the management interface should reload.
15. If everything went well - your system should show System version as 1.00.07
16, Use your newly upgraded modem/router!
17.Remember: Disable WPS in advanced menu, Disable UPNP
18.Now the modem will not be pingable from internet. All open ports were closed

Happy upgrading!              Dlink 2750U Version - i1 Firmware link-1    link-II


Troubleshooting for Broadband Speed
List of Checks in Modem
1.LineSNR -----it must be stable and greater than -8db is preferred.
2.LineRate------Must be slightly higher than Plan speed
For example, 4Mbps plan line rate must be greater than 4400Kbps.
       otherwise customer will get 3.6Mbps only 
3.Annex-M dsl modulation
Set modem in ADSL2+ Annexure-M modulation to improve SNR.
For long distance connection use G.Dmt modulation.
4.Set DNS-relay-in-modem -- If DNS is set it will be relayed to wireless devices.
   (Normally it is available in LAN > DHCP setting)

5.Set DNS-in-PC
To improve browsing speed
To avoid page not found errors

6.Disable-WPS in Wireless
In DLink modem it is available in Advanced >wireless>WPS-Disable
In Tp-link it is available in Interface Setup>Wireless>"Use WPS=No"
This setting is very important to get rid of misuse of broadband.

7.a Deactivate-UPNP/CWMP/Tr069
universal plug and play UPNP normally available in "ADVANCED"
To avoid hacking from the internet.
   b. Activate 'ACL'
in adavanced menu to block modem access via internet

8.Use Best ,Secured and latest version browser.
Mozilla Firefox & ComodoDragon (very secured & uses own DNS)

9.Disable all Add-ONs except "java" and "Flash"

Following are examples of Junkwares to be removed:

  • Ask Toolbar
  • Babylon
  • Browser Manager
  • Claro / iSearch
  • Conduit
  • Coupon Printer for Windows
  • Crossrider
  •           Delta Search
  • Facemoods / Funmoods
  • iLivid
  • IncrediBar
  • MyWebSearch
  • Searchqu
  • Web Assistant
  • To remove all above junkwares use ADWCleaner
  • (

10.Install-HOST-file to block advertisements
Available in

11.Dslam Line Profile attached to the port (check line rate & SNR before book the case)
 Book a case to NiB to change line-profile thro

-Customer may choose a plan from 8Mbps to 24Mbps.
-Customers in old 2/4Mbps plan must be migrated to new PLANs
-Maximum download rate depends on line rate, SNR & BB-plan also.
-Upload depends on ADSL/VDSL modem and ANNEX-M mode.
In Annex-M mode we can go upto 2Mbps upload for ADSL modem.
For VDSL modem it can be upto 24Mbps.

13.MTU -Maximum transmission unit.
Normally the values are 1492,1452,1400 or 0
To verify MTU, open the site
The site will not load if MTU is wrong, if so try different values.
MTU problem mostly exist in Netgear,Belkins,Zyxel modems.

In some DSLAM will not load fast.
If so check the speed by playing youtube video, if no buffering, speed will be Ok.
If customer not convinced, change the indiactor to some other DSLAM (like sterlite/Huawei etc)
Please note that if speedtest site is full of advertisements, then install Host FILE first.

15.Disable-Apps in Win8/10 -Windows 8 and above installs many apps like weather, news,sports etc
Disable or uninstall these application to avoid interference in browing.

16.Dont use autoUpdate of windows/ Antivirus(set as manual update)
This is to avoid automatic downloading in background.
To disable autoupdate - RUN>services>windows update>disable

17.All above settings to be done in all PCs in a network environment.

18.Ping TEST the DSLAM for packet loss.
Test through NIB helpdesk portal Menu 4E

19.Trojan attack -Internet virus

Trojans normally attacked thro LAN adapter, Browser add ons and as a service
Indications of trojan attack:
a,Continuous flickering internet light when no browsing or downloading.
b,Close all internet apps like chrome, IE, firefox ,outlook etc
Now thro command prompt give the command - C:\ netstat  -an
This will list of connections established with foreign address.
Too many foreign address ie, more than 10 means PC may be attacked with Trojan.
Ignore foreign address in the range like 10.x.x.x ,127.x.x.x,192.x.x.x.

How to remove trojans ?
1. Disable startup application and restart.
2. Install malwarebytes software

20.Computer settings:
     a. Set DNS manually
     b. Uncheck all other tick marks except TCP4 in LAN Properties.
     c. Disable startup applications  Start > Run > msconfig
     d. Disable startup services Start >Run > msconfig >Services tab
                          > Check 'Hide all Microsoft apps' >disable all   

Finally call NIB in-charge for further help.

Security issues in Wireless Network (Wi-Fi).
(Applicable to Broadband modem, Wi-Fi-Data card and Mobile AP)
With traditional wired networks, it is extremely difficult for someone to steal the bandwidth but the big problem with wireless signals is that others can access the Internet using some hack tools to access customer broadband connection even while they are in a neighboring building or sitting in a car that’s parked outside the building.

Why wireless security is important?
1. It will increase monthly Usage.
2. Customer will get reduced speed since sharing the same internet connection with other users.
3. It can create a security hazard to customer computers and anyone can access personal files through wireless network.
4. illegal access to internet create issues to customer.

How to secure wireless network?
1. Change default SSID in the wireless modem /Datacard.
2. Change default password, Security PIN etc.
3. Disable WPS.
4. Use wireless encryption “WPA2-AES
5. Pre-shared key should not be a mobile number or 1234 etc..
 (use pass phrase something like=’care@share1’)
6. Enable MAC address filter (Optional for more security).

How to verify Wire security?
1. Check who is connected to the wireless modem can be seen in
Status>Local Network or DHCP or ARP
Install the tool “WPA Security tester” for Android Phones.
(Caution: Don’t miss use this tool for any other purpose)
Click here to download WPA-TESTER

SNAP SHOT of ADSL modem settings and WPA-tester apps: