Internet Explorer DNS cache location

2

It is known that IE has its own DNS cache. I want to clear it at times. I know that I can do it by clearing browsing history in IE settings. But I'm looking for automatic method, so the location in file-system (or whatever) would be very helpful.

y0prst

Posted 2011-12-12T16:21:10.937

Reputation: 143

Answers

1

The accepted answer is wrong. IE does have its' own DNS cache, which can not be managed by ipconfig.

Refer to https://support.microsoft.com/en-us/kb/263558

SUMMARY In earlier versions of Internet Explorer (Internet Explorer 3.x), DNS host entries are cached for 24 hours by default. In many cases, this is too long. During this period, some host entries stop working because of change in the IP address of the remote server that was initially resolved.

Internet Explorer 4.x and later versions modify how DNS host entries are cached by decreasing the default time-out value to 30 minutes.

MORE INFORMATION WARNING: If you use Registry Editor incorrectly, you may cause serious problems that may require you to reinstall your operating system. Microsoft cannot guarantee that you can solve problems that result from using Registry Editor incorrectly. Use Registry Editor at your own risk.

In some cases, this new time-out setting is too short. If your environment has a number of clients that are connecting and are all performing DNS lookups every 30 minutes, you may experience an unwanted increase in network traffic. To modify this behavior, make the following registry change: 1.Start Registry Editor. 2.Locate and click the following key in the registry: HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings

3.On the Edit menu, click Add Value, and then add the following registry values: Value Name: DnsCacheTimeout Data Type: REG_DWORD Radix: Decimal Value: (time in seconds)

Value Name: ServerInfoTimeOut Data Type: REG_DWORD Radix: Decimal Value: (time in milliseconds)

4.Quit Registry Editor. For example, to set the time-out value to 10 minutes, use a value of 600 seconds.

Note You must use both the registry values listed in step 3 to control the Internet Explorer internal resolver cache mechanism.

Note These settings apply to Internet Explorer and Asynchronous WinInet calls only. These settings do not apply to Synchronous WinInet calls.

user1748640

Posted 2011-12-12T16:21:10.937

Reputation: 26

Could you possibly quote the relevant sections of that KB article? – Burgi – 2016-04-29T11:47:14.613

Refer to this one as well: For performance reasons, WinINET caches address lists using an in-process memory cache; this cache allows reuse of recently used addresses without resolving them again. DNS resolutions are also cached by Windows’ DNS Resolver itself, but retrieving them from the Windows cache requires an RPC call, which, while much faster than issuing a DNS request on the wire, still takes some time. https://blogs.msdn.microsoft.com/ieinternals/2012/09/26/braindump-dns/

– user1748640 – 2016-05-01T02:37:48.353

0

The MS KB article 263558 only indicates how to change the timeout of the DNS entries. It doesn't indicate where they are stored.

However, I had a user whose IE11 kept encountering ATT's hijacking/redirection (DNS Assist helper) which was triggered while accessing an internal VPN site - but not all internal sites.

Clearing IE11 cache from within IE did not help.

Google Chrome did not experience ATT redirection - it found the internal site, thus confirming IE was maintaining its own DNS cache.

Within IE11, go to Tools > Internet Options > Browsing history (section) select Settings (button). View files (button) and keep that Windoze Exploder (WE) window open. In Win 7 it is “C:Users\USERNAME\AppData\Local\Microsoft\Windows\Temporary Internet Files\”

Exit IE11 and delete all the files (cookies) in that above WE directory. In my case I reopened IE11 and it was able to access the problem internal site.

I'm not saying that is definitely where the IE DNS sites are stored as it may have been some other cached browser data that prevented the problem site from being accessed.

By the way, manually clearing the files in that directory is necessary at times because it appears that if cookies are corrupt clearing the cache from within IE doesn't always clear the corrupt cookies. I found that out from another IT technician who has had that experience.

If the problem internal VPN site was due to a corrupt DNS entry, it may be that manually clearing the cache took care of the suspect corrupt DNS entry, if they really are stored there.

I just found another storage place, though it may not be DNS either, from the directory above it's up one level and down to %userprofile%\AppData\Local\Microsoft\Windows\INetCache\ That came from https://stackoverflow.com/questions/854412/internet-explorer-cache-location

PReinie

Posted 2011-12-12T16:21:10.937

Reputation: 53