I was attempting to install some software recently (a few hours ago, actually) and I kept getting a message saying “The installer has encountered an unexpected error installing this package. This may indicate a problem with this package. The error code is 2755.” while installing the software. So I searched the internet for an answer and came up with all sorts of links:
- http://support.microsoft.com/kb/q251274 (Error Message When You Attempt to Install Program Using Windows Installer)
- http://support.microsoft.com/kb/217714 (Setup appears to stop responding and you receive an “Internal error 2336” or an “Internal error 2755” error message when you install Office 2000)
- http://support.citrix.com/article/CTX110991 (Error: The installer has encountered an unexpected error installing this package … when Interactively Installing an EdgeSight Agent)
- http://support.sourcegear.com/viewtopic.php?t=181&view=previous&sid=d59a03db75c3a915a6c3742ca9c4f71f (Internal Error 2755. 3)
Anyway, most seemed to suggest that the problem lay with incorrect permissions being set on the file system. So, I went through the file system and checked the permissions as per the Microsoft knowledge base article detailing the problem with the Office 2000 installation. Everything set correctly, I tried again. No luck.
I burned the MSI file to a CD and it worked (CDs don’t use NTFS and its permission system). So, it was something definitely to do with the permission sets.
I downloaded FileMon from the SysInternals website so have a look further at what it was doing. I discovered that it was getting an Access Denied on a file in the Temp directory. (The setup program dumped an MSI file in the temp directory during installation) The problem was, it appeared to be attempting to open the file as NT_AUTHORITYSYSTEM. That account has more rights than the Administrator account, it basically is an Access All Areas account… And it was being denied access!
After some further experimentation, including restoring a system checkpoint back a couple of days, it still wasn’t working. Then I noticed that the temp folder was green which indicates that the contents were encrypted. (I experimented with file encryption a few months ago and had since forgotten about it).
To cut a long story short, I removed the encryption flag on the Temp directory (and spent a couple of minutes waiting for it to decrypt everything) and tried the installer again. It worked!
I don’t know why the fact the folder was encrypted had anything to do with it, but it worked once decrypted. Weird….
NOTE: This entry was rescued from the Google Cache. The original date was Sunday, 15th October, 2006.
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install software unexpected error microsoft knowledge base permission msi ntfs filemon sysinternals access denied encryption
Original comments:
Windows Installer works in two phases – an ‘immediate’ phase in which it generates a script for what to do, and a ‘deferred’ phase in which it actually does the installation. The immediate phase runs under the launching user’s credentials, but the deferred phase is run by the Windows Installer service, which runs as LocalSystem.
If the script is written into an encrypted folder, it will be encrypted using your encryption key. The service, running as LocalSystem, will not have this key, or the recovery key (which is owned by the administrator) and will be unable to read the script.
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I had a similar issue with installing a HR and Payroll update for Dynamics. The exe had embedded .msi and .ini files, which I used Winzip to extract “prior” to running the install. After running the .msi directly, as opposed to just running the compressed .exe, I was able to get passed the error.- So extract first manually with Winzip then run the .msi directly.
I just found this solution for the error 2755 as I was having trouble installing Trend Micro Internet Security 2008 for the same reasons. I too have now installed the files from the CD into a folder that is not encrypted and it now installs ok. It certainly does cause problems installing the install files into an encrypted folder as I had done. Thanks for the clue to the problem!!
Well, what can I say but THANKS a lot!The encryption issue was indeed the problem, not only with the folder but the msi file as well (got the file from the developer’s download site), but even after moving it to an unencrypted folder, the msi file retained the encryption and hence causing the installation to be aborted anyway.After removing the flag (File Properties>Attributes: Advanced Options in case somebody may wonder how)Best regards and thanks again for a greatly clarifying solution!
For me it was the My DocumentsVisual Studio 2005Projects folder and all subfolders that were encrypted. Decrypting my project folder and subfolders fixed the problem.
i had so big trouble in installing one software which i downloaded to my desktop…it always showed error 2755 and i tried again and again only to get more and more desperate…At last ,fed up and i googled to find this page….only to find my folders in desktop are encrypted!!!! Now it all got fixed ,thanks a lot
Thank you very much!!!By decrypting the folder where the .msi file was located solved the internal error 2755.I right clicked the folder and selected ‘decrypt’. Waited for it to finish and re-started the install – worked OK!!!Simple solution once you know about it.
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Simple solution once you know about it. i am on your side
What if it’s a single file that is on a hard drive where all files are encrypted? Will changing the install file to “Encrypted” yield the same results?
@Jack It still won’t work. See Mike Dimmicks note above. It doesn’t matter that everything on the Hard Drive is encrypted (unless you are taking about Vista’s Bitlocker which I don’t know about) because the encryption is at a file level. Each file is encrypted with the encryption key of the user that created it (or encrypted it). The installer runs in two phases. The first phase as the user that launched it, the second as the Local System. This means that the temp files created in the first phase will be encrypted with your key. However, in the second phase the installer will fail because it will try and decrypt it with the Local System key.
I fixed this error by changing permissions on my Temp folder. My temp folder is set on my D drive and I changed the permissions for the System Account to This folder, subfolders and all files.Right Click Temp folder and select Properties.Click the Security Tab and then the Advanced Button.Under the Permissions Tab click the System user and then Edit.For Apply onto, choose “This folder, subfolders and all files”. Mine was set to “This folder.”
how if you are trying to install from the CD?
@mchiks This was 2 years ago now, so I don’t remember exactly.I’m guessing that the set up program when run from CD realises it is a read-only media and so doesn’t copy the file to the temp directory. When it is being launched from the hard disk it copies the files to the temp directory so it can have control over them. But, I reiterate, that is only a guess.
I encountered this issue with Vista. Here is my observation:– change the permission of Temp folder dosen’t work- change the permission of the folder where the file I intend to execute/installed work
just right click on the file name>properties>advanced and unclick “Encrypt contents to secure data”fixed
This thread was a life-saver for me. Typed ‘Internal Error 2755’ into Google and this was the first hit.Solved my whole problem: once I unencrypted my ‘dowload’ directory, my downloaded program (.msi file) installed without a hitch.Many many thanks!
I got this problem, when I was trying to install TortoiseSVN (msi file downloaded from internet). Thanks a lot for the solutions mentioned here…I removed the encrypted flag for the msi file and it just worked fine..thanks a lot again!!!
I had the same problem (Error 2755 when trying to install Visual Studio 2005 Service Pack 1 – The problem was solved by giving MORE FREE SPACE on the hard disc.the official requirements are for 6 GB (!!!) – the reason is that the installer extracts from 440MB to almost 1GB
Thank you so much, everyone, for posting these solutions!I have Win XP and for me the solution was to decrypt the folder that contained the install files, etc. So easy! I had been searching in vain for a solution for a long time. Tonight I changed my search term in Google to ’cause of Windows 2755 error’ and arrived here! Yay!
I’m still getting the error.. not encrypted, permissions checked, took ownership, plenty of disk space, download dir not encrypted, destination not encrypted, downloaded another installer. Trying to install vs 2005 sp1.
I’m glad you all encountered this issue before I did and were gracious enough to share your solutions! I doubt that in a million years I would have figured it out and I was not getting a response from the folks at Trend Micro. It scared me a bit that the software had uninstalled the earlier version of my security software but wouldn’t install the update.Unencrypting the setup folder that that install progam created worked like a charm. Thank you all for shedding light on my dilema!!
Hey, heartfelt thanks for the solution and explanation of what was going on. I support a small software product that I created and a customer ran into this issue. This information saved me a lot of time and grief.
A massive thanks. This has saved me at least 6 hours work.
Installing VS 2005 SP 1 Internal Error 2755 .firstly you can install Update for Windows Server 2003 (KB925336),you can download it here:http://www.microsoft.com/downloads/en/confirmation.aspx?FamilyId=8EFFE1D9-7224-4586-BE2B-42C9AE5B9071&displaylang=enand then you install Visual Studio 2005 Service Pack 1,the problem will be solved .
I just copy my software to desktop, and double click it, wow, it works!
A solution might be to create this: C:\Windows\Installer, it might be non-existent or inaccessible.
Guys yall are going to complicated lol. What i did which was really easy is I placed SteamInstaller.exe into a seperate folder went to the properties, selected decrypte all files,subfiles,and folders let it do its thing then i was able to run the installer int he folder. No need to unencrypte all your encrypted files.