How to fix unarc.dll or Isdone.dll errors

Unarc.dll or Isdone.dll errors are quite common for Windows 10, 8 and Windows 7 users. The fact is, they are almost one and the same error. These errors can occur when you, for example, download an archive from the Internet and try to unpack it, or try to install a downloaded game with the Innosetup installation program.

First thing to try: disable your antivirus and try running the program again. Recently (2016) some users report that turning off Windows 10 an 8 SmartScreen filter helps as well. If that works, scroll to the bottom of the page and use the share buttons.

Second: if the path to the file that won’t run has non-latin characters in it, move file to another location, to C: root folder, for example.

Unarc.dll error code -1 Archive Data corrupted

Unarc.dll error code -1 Archive Data corrupted

If you search for a fix on the Internet, you’ll find many “unarc.dll fixer” programs, but none of them work. I highly recommend that you not download any of these applications. Working for quite a while as an IT support engineer, I can give you some helpful advice on how to fix the unarc.dll and Isdone.dll errors.

Common error messages for unarc.dll and Isdone.dll

  • An error occurred while unpacking: archive corrupted unarc.dll returned an error code: 1, 6, 7, 12 error: archive data corrupted (decompression fails)
  • ISDone.dll error
  • An error occurred while unpacking: archive corrupted!
  • Unarc.dll returned an error code: 7
  • Unarc.dll returned an error code: 6
  • Unarc.dll returned an error code: 12
  • Unarc.dll returned an error code: 1
  • ERROR: archive data corrupted (decompression fails)
The error may happen during the installation of Resident Evil, Crysis Warhead, Day One, Assassin’s creed and other games.

Try the software on another PC

These steps may seem strange, but you should try them if you really want to fix the error:

  • Move the file from the computer on which the error occurred to another PC. (Use a USB flash drive or local network. Do not just download it from the same source on the Internet.)
  • If the file works, then something is wrong with the first PC. There may be several causes of the problem. For example, there might be system or RAM issues.
  • If there’s still an error on another PC, try the same file, directly downloaded to the second computer from the same source on the Internet. Try unpacking or installing it.

If the result is: “Wow! It worked on the second PC! How can that be?” then you should strongly consider RAM problems on the first machine, as this is a very likely cause. For some reason unarc.dll and Isdone.dll errors are most often caused by hardware issues, and are not Windows 7 or Windows 8 problems.

If neither troubleshooting method worked, we should deal with the source of the file. If possible, try another source for the program. If not, you may try using Universal Unpacker free software, which you can easily find on the web. With this utility, it’s sometimes possible to unpack installation packages that seem to be corrupted.

Fixing unarc.dll error caused by RAM problems

Error occured when unpacking. Unarc.dll error code -1

If you come to conclusion that your RAM is the cause of the unarc.dll error, then the only thing I can suggest is to remove memory modules one by one (don’t do it if you don’t know how) and test the program again. If you find it works when a specific RAM module is removed, you will have found the problem.

Comments (46)

  • Youssef

    Thanks it really helped me 😀

    Reply

  • Lex

    I’ve already installed the program some time ago, then deleted it, and now I wish to install it again. It fails! Showing something like “decompression fails: archive corrupted”.
    RAM error? Absolutely not: the same error is shown on both my PC’s.
    Archive corruption? No, I’ve checked it has right hash and saying more it already has been installed.

    Senseless article.

    Reply

    • Fix PC New York

      As I’ve said it may be corrupt file downloaded as well and the first thing one should try is to find another source for it

      Reply

  • VampireRedeemer

    Hope RAM is the problem in my case and nothin’ else. Thanks man!!! can’t wait to try!!!

    Reply

  • John

    How to remove ram modules? And what will happen if i do?

    Reply

  • Juvela

    I turned off my virusdetection program and that worked. After installation I turned it on again 🙂 And ran it too.

    Reply

    • Lucas

      Thank you very much Juvela, that solved my problem! 🙂

      Reply

    • qusai safa

      u are great ,the problem solved thank u very much Juvela

      Reply

    • isuru

      thak u sooooooooooooooooooo much 🙂

      Reply

  • Hsr

    well well I moved the file to C drive root and it worked..

    Reply

  • gamer123@AJay

    if the problem still occurs all you have to do is this
    1. download ccleaner
    2. after installation click on run
    3. now go to your personalization menu
    4. then select windows classic theme
    5. install the setup file that shows this error
    6. this time it would work perfect
    7. WORKED FOR ME !!!!!!!!!!

    Reply

  • ngureco

    A very sensible article. just disable the anti-virus and everything works just fine. Keep up the Good work!

    Reply

  • danossh

    Hello, I Need help regarding this error -14 while decompressing
    Unarc.dll returned an error code: -14

    Reply

    • Fix PC New York

      It’s the same error. The most often working ways to fix the error: 1) move the files to the C: disk home folder, 2) disable your antivirus

      Reply

  • gaurav

    what about Unarc.dll returned an error code: -11
    it came while i was installing a game
    is there any way to fix it??

    Reply

  • markpaul

    it works just change the installation path and i tried to turn off my anti virus but i think anti virus is not the issue 🙂 thanks

    Reply

  • Umbral

    My error 14 was windows defender. I dont know it was on. Disabled and worked.

    Reply

  • srikar

    Guys help me
    Unarc.dll received error code 12 I tried
    Taking out antivirus and also keeping isdone.dll
    And 232.Dll into system 32 and syswow64
    Plz help

    Reply

  • ferhat

    I had same problem with my Max Payne 3 and i’m solved it by showing setup files in virtual drive by mounting iso file on Daemon Tools. You should try this..

    Reply

  • Must

    “disable your antivirus ”

    yeahh its working thanks 🙂

    Reply

  • Jeswin Daniel

    Thanks for your help. It works fine after disabling anti-virus.

    Reply

  • B

    Ok, so can you give me some help if it’s an “error -11” ISDone.dll error?? I don’t see that one on your list, and haven’t been able to find anything about that on the web. Please help me.

    Reply

  • Raunak

    Thanks! I was installing Hitman absolution when i got the error “unarc.dll” Compression method not verified. I disabled my anti-virus as you said and it worked. I was able to install the game. Thank you.

    Reply

  • xander

    I’ve encountered error code -7, disabling antivirus doesn’t work. please help me guys -_-. I’m installing devil may cry 4 on windows 7

    Reply

  • samir

    i was installing the game ‘black ops 3’. then i saw it. what can i do naw?

    Reply

  • jacob

    still didnt work for me 🙁

    Reply

  • Daulat

    GTA 4 installing error

    Reply

  • Nimesh

    I have problem unrac.dll returned an error code:6 how to fix i can’t

    Reply

    • Fix PC New York

      First try disabling your antivirus and Windows SmartScreen Filter

      Reply

  • yoossf

    what about unarc.dll error code 14

    Reply

    • Fix PC New York

      same issue

      Reply

      • Sai Swaroop

        unarc.dll error code:-14
        ERROR:this is not FreeArc archive or this archive is corrupt
        Can u please help me on this to resolve this error if ur issue is resolved.

        Reply

  • jeremy

    thank you soooo much. I turned off my windows defender and now its working

    Reply

  • Ben

    It works for me after turning off ‘Windows defender’ and ‘Windows Smart Screen’.
    Be sure above 2 services are turned off.

    Reply

  • Abbas

    Hay everyone ! ( i have a solution )
    I had this problem for a week and i was really mad about it.

    I tried all the methods on internet ( youtube ) but nothing worked .

    I just changed my hardisk drive and and now i have no errors all games installed properly .

    Reply

  • Felipe

    Turning off the Windows smartscreen worked here on Windows 10, and i disabled Windows defender too.
    Thanks for the advice man!

    Reply

  • sunny shekhar

    that software didnt work for me .i am trying to install wwe 2k16 getting erro “unarc.dll error code -7”

    Reply

  • 001

    im having the same problem in COD black ops 2

    the difference is

    Unarc.dll returned an error code: -11

    Reply

  • Brian

    Disabling the antivirus worked for me as I was installing my PES 15. This articke is quite helpful. Thanks a lot

    Reply

  • Fbian

    disabling windows defender helped 🙂

    Reply

  • Luca

    Thank turning off Windows 10 antivirus worked for me 🙂
    now i can install Far Cry 3

    Reply

  • harry

    Paused anti-virus & disabled smartscreen filter…it worked!!
    thanks

    Reply

  • icycles23

    anyone has solution for error 7 yet ? im trying to install prototype 2

    Reply

  • Hrithwik sarang

    While installing PES2015( corepack )an error occurred.
    “ISDone.dll”
    “An error occured while unpacking:Does not match cheksum!
    Unarc.dll returned an error code: -12
    ERROR:file\ dt15.cpk failed CRC chek”
    Why this happen?
    please give the solution.

    Reply

  • vipushan

    for error 11 just make sure you have LOTS of space on your drive. worked for me

    Reply

  • potter

    I installed it earlier and the game installed perfectly but the second time i tried installing it this error shows up on the same PC, Please Help!

    Reply

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