Technology in terms you understand. Sign up for the Confident Computing newsletter for weekly solutions to make your life easier. Click here and get The Ask Leo! Guide to Staying Safe on the Internet — FREE Edition as my thank you for subscribing!

What are those strange folders in my Temporary Internet Files?

Question: My Temporary Internet Files show a lock and cannot be deleted, I’m thinking this is a problem. There are 23 files; eg. 8XE96F4H, ALFCPSNU, DUXEMEN9 etc. I have Googled some of them and they show a website in Japan but some show nothing. Norton AV doesn’t catch(see) them, neither does Spybot. So far I don’t see them causing problems but I don’t like this at all.

First, let me put your mind at ease. There’s no problem.

They’re definitely oddly named directories, but it’s just Internet Explorer being … well, being Internet Explorer.

Here’s what’s going on …

Become a Patron of Ask Leo! and go ad-free!

As you browse the internet, IE “caches”, or keeps local copies of, lots of the files that are downloaded as part of your surfing. For example the images that might be part of a web page are downloaded and placed in the cache.

Why? So that when you return to that page, or another page that references the same image, IE doesn’t have to download it again. And again. And again.

The result is that your browsing experience is much faster.

Did I mention that there could be a lot of files? Thousands of files. Thousands and thousands of files.

Various hard disk file systems (FAT, FAT32, NTFS, and perhaps others we haven’t even thought of yet) have different limits and performance characteristics when you place a large number of files in a single directory. But they all do relatively well with lower numbers of files. Rather than throw all the files into a single directory, IE creates several subdirectories, and spreads the files among them.

So why the odd names? To be brutally honest, I’m not sure. There may be some very geeky reason that it makes the software elegant or more effective, I suppose. Personally, I’d have chosen more normal names, in case real people end up actually seeing them and getting confused or concerned. And of course your question is not uncommon, and shows that’s exactly what happens.

And there’s the key; these directories were actually never meant to be viewed directly by real people. The intent is that Internet Explorer would manage them. In fact, Windows Explorer even goes the extra mile to hide those directories by making it look like all the files in them are actually directly in Temporary Internet Files.

If you view the “Temporary Internet Files” directory in Windows Explorer, you’ll see that it contains lots of files. (You may have to configure Windows Explorer to “Show hidden files and folders” – I touch on that in Part 2 of How should I set up my computer?) However, if you open up a Windows Command Prompt, and navigate to that same directory, you’ll see the list of subdirectories with funny names and a file “index.dat”, which is what IE uses to keep track of what files are where in the subdirectory. The actual files you saw listed in Windows Explorer are actually distributed within the subdirectories here.

I wouldn’t expect Norton or Spybot to say anything because everything is as expected.

Confusing, perhaps, but as expected.

Do this

Subscribe to Confident Computing! Less frustration and more confidence, solutions, answers, and tips in your inbox every week.

I'll see you there!

14 comments on “What are those strange folders in my Temporary Internet Files?”

  1. Leo – I searched my “Temporary Internet Files” directory in Windows Explorer and found over 1000. A lot of these had 20 or more individual folders containing over 500 files each and used up over 20MB of disk space each. Some of the files within the folders showed a creation date in 2004 (for example) and an expiration date into the year 2010. That sounds kinda permanent to me. How does Windows or IE determine that a file or folder should be temporary vs. permanent? If it’s labeled temporary, why would it last so many years? Are all temporary files or folders safe to delete? If some temporary files or folders are crucial to proper operation of one’s system, (ie: hidden from view) why aren’t they permanent? I’m a little confused on this. Thanks for clarifying.

  2. Well, there’s temporary, and then there’s temporary.


    Anyway, you can certainly delete the contents of your Temporary Internet Files directory tree. IE will start rebuilding it the next time you run it. It’s pretty much equivalant to flushing your cache and deleting your cookies from within IE. Your browsing experience will slow down a little on some sites as it rebuilds the cache, and any logins and the like that you have saved in cookies will simply need to be reentered.

    But there’s nothing crucial to operation in Temporary Internet Files.

  3. How do I get into these hidden files to see the websites my girlfriend has viewed. I think she is cheating and know she deletes the cookies.

  4. I have been using the Internet Options dialog to eliminate Temporary Internet Files, regularly, at the end of each computing session, and it has appeared to work fine…until, at the beginning of the next session–before connecting to the Internet–I run a SpySweeper scan and note that it spends an awful lot of time scanning files which have somehow mysteriously ‘reappeared’ (?) in the Temporary Internet Files directories. What’s going on? I thought they were all cleared out! Can you explain this?

  5. I am a mother with 4 children. My husband has recently been gone non-stop. I think he is having an affair. He doesn’t let me work so I don’t have the money to hire a private detective. He is constantly on his email when he is home. When I check them, he has deleted his emails. Is there any way to see those emails through the temporary internet files? I have tried to open them, but they just won’t open.

  6. Hi, I was wondering why the size of my temporary Internet Files are getting bigger even if I’m not surfing?

  7. Hi leo i’m wondering is it possible to put files into the temporary files directory….as i copied the files downloaded for a game i play & i deleted the Temp’s & want to paste them back in but i wont let me

  8. temporary internet files properties: contains 1450 files and 35 folders Read Only box is checked and so is Hidden except I cannot uncheck the hidden. I have check show hidden files and folders but files i.e. jpegs are not showing up there using Vista, as they did using XP. Any ideas?

  9. Dear mother of 4. Unless he accesses his mail through the web, none of his emails would be stored in the IE temp file. Since you weer able to see that he deletes his emails it seems he uses an email program. Some email programs save a backup file and others don’t actually delete the emails until they are compressed. So my answer to you is a definite I don’t know. My advice is to go to the local computer store and ask the guy there. Usually they are helpful and can ask you the right questions to find out how to solve your problem.

  10. What is this temp file (JETA459.tmp) and can I delete it? It says it won’t delete because a program is using it but I have no programs running.

    If you have Windows running, you have programs running – even if none are listed. (Windows itself is a program, and uses additional programs to do its thing.) I’ll point you at this article to start: How can I find out who is using a “file in use”?


  11. An alternate explanation:

    Most Web pages are composed of more than just the file for its text. For example, each photo requires a separate file. For speed, Internet Explorer stores these files locally in the Temporary Internet Files. This is called a browser cache (other browsers, like Firefox, use their own caches, stored in different folders). When you request a Web page, Internet Explorer looks in its Web cache for the files that compose any requested page. If they are not found, it finds them on the Internet using their address (URL). You can see that using the Web cache is faster on average, since viewing previously-viewed parts of pages will be much quicker (a local file read from your disk is faster than a remote file read using the Internet communications channel).

    In order to speed up even the lookup of the file name of a part of a Web page, any Web cache is structured for “hashed lookup” (or “hash code lookup”).

    Here’s how that works: The filename is first processed to produce a random-looking name called a hash code. There are only a limited number of these hash codes, whereas the number of filenames is almost unlimited. Next, the hash code is used to find a short list of filenames that are already in the cache (of course, this list will initially be empty). Since the list is short, finding the filename is fast. If the filename is not found, it is stored in the cache and the file itself is read from the Internet.

    The Temporary Internet Files folders (“Content.IE5” is a folder containing the index.dat file and strangely-named folders containing the actual files that are used to display Web pages) are not actual folders in the file system. They are objects that are actually all stored in a single file (for efficient access) and made to look like folders and files by the File Explorer for convenience, so they can be individually deleted by the user if needed. They represent the hash coding mechanism (each strangely-named folder is one of the shorter file lists described above).

    I’ve glossed over many details in this description, but it gives the basic ideas.

  12. I understand that IE will store these temporary internet files in order to speed up browsing. However, I’d think that this would only be the case if I was using IE as my browser. Why does IE store temporary internet files on my computer while I browse with Firefox?

    Because the “guts” of IE are used for much more than web browsing. More in this article: Can I remove Internet Explorer if I never use it?

  13. Pc does not have room any more…problem…scratch disk full…how do I find the folder that has the files from the scratch disk so that I can delete them…also how do I keep scratch disk turned off?


Leave a reply:

Before commenting please:

  • Read the article.
  • Comment on the article.
  • No personal information.
  • No spam.

Comments violating those rules will be removed. Comments that don't add value will be removed, including off-topic or content-free comments, or comments that look even a little bit like spam. All comments containing links and certain keywords will be moderated before publication.

I want comments to be valuable for everyone, including those who come later and take the time to read.