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I type a web address correctly. Firefox then changes the address to another site.

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After typing and entering the correct address of a secure government site I frequently visit, Firefox has today started to add in additional address data ".csda." and attempts to access the new site. The new site does not load, and Firefox returns the error message "Server not found". So far the problem occurs only with this one site. This behaviour does not occur when I use the Microsoft Internet Explorer browser. Can anyone help please.

After typing and entering the correct address of a secure government site I frequently visit, Firefox has today started to add in additional address data ".csda." and attempts to access the new site. The new site does not load, and Firefox returns the error message "Server not found". So far the problem occurs only with this one site. This behaviour does not occur when I use the Microsoft Internet Explorer browser. Can anyone help please.

Chosen solution

If you feel like digging into it further, you can open the web console below the page (press Ctrl+Shift+k) then try the URLs again in that tab. Various lines will collect in the console. If you scroll back up and click the first URL, you can check the response to see whether it is redirecting. In the Response Headers, you would see one that says Location and lists the new URL.

Note that sometimes a redirect that appears to behave randomly indicates a hacked website. This would be more likely if you are navigating to the site from a search results page, since hackers often fly their redirects under the radar by only attacking visitors using search engines (under the radar because the webmaster never accesses their own site that way).

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Start Firefox in Safe Mode to check if one of the extensions (Firefox/Tools > Add-ons > Extensions) or if hardware acceleration is causing the problem (switch to the DEFAULT theme: Firefox/Tools > Add-ons > Appearance).

  • Do NOT click the Reset button on the Safe Mode start window.

Do a malware check with several malware scanning programs on the Windows computer.
Please scan with all programs because each program detects different malware.
All these programs have free versions.

Make sure that you update each program to get the latest version of their databases before doing a scan.

You can also do a check for a rootkit infection with TDSSKiller.

See also:

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Tried changing to No proxy - did not work

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Strangely enough the problem occurs with all versions of Firefox on any of my different computers, including the Dell tablet. The problem occurs with only this one site , so it looks like the problem is with the site. I shall contact them. Many thanks for the responses, all of which I have tried, but to no avail.

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Seçilmiş Həll

If you feel like digging into it further, you can open the web console below the page (press Ctrl+Shift+k) then try the URLs again in that tab. Various lines will collect in the console. If you scroll back up and click the first URL, you can check the response to see whether it is redirecting. In the Response Headers, you would see one that says Location and lists the new URL.

Note that sometimes a redirect that appears to behave randomly indicates a hacked website. This would be more likely if you are navigating to the site from a search results page, since hackers often fly their redirects under the radar by only attacking visitors using search engines (under the radar because the webmaster never accesses their own site that way).