The installer encountered an unexpected error ‘Error 2755’ [Solved]

The error with code 2755 when trying to install something via Windows Installer states that the server returned an unexpected error when attempting to install a package. Into plain English, it means that there is a serious error with your attempt of installing the software and you will most likely fail to do so.

You might get this error with a number of different installation files, and it isn’t their fault. The error is related to Windows’ installer folder and certain permissions, which may get messed up due to a number of reasons, for example malware, and not allow you to install anything on your system.

There are several solutions that you can try, and almost all of them deal with a different aspect, which means that you may need to try all of them before finding the one that works for you. Keep in mind that they are easy to try, you just need to carefully follow the instructions in the methods below, and you can install the software you need in little to no time.

Method 1: Add an Installer folder in the Windows directory

This error has been often connected to the fact that the Installer folder is missing from the Windows directory in your OS partition. We are going to assume that C: is the partition where your operating system is installed.

1. Open My Computer or This PC, depending on which version of Windows you have, and open the C: partition (or the partition where your OS is installed). Open the Windows folder inside.
2. Right-click anywhere on empty space, and select New, and then Folder from the menu. Name the folder Installer and save it. Reboot your system and try installing your software again.

Method 2: Check if the setup file is encrypted

If the setup of the software you’re installing is encrypted, you will most likely face this error. However, checking this and removing the encryption is fairly easy.

1. Locate the setup file, right-click it and select Properties from the dropdown menu.
2. Click on the Advanced button in the Attributes header.
3. Under the lower header, Compress or Encrypt attributes, make sure that Encrypt contents to secure data is unchecked. Click OK twice to close the dialog windows, and try installing the software again.

Method 3: Add the SYSTEM user in the installer

1. Again, right-click the installer file and select Properties from the dropdown menu.
2. Navigate to the Security tab and press Edit.
3. Under Group or user names: press Add, and type in SYSTEM, with caps, and hit OK.

Make sure that the permissions are all set to Allow for the SYSTEM user. Close the dialog boxes by pressing OK on them. Try installing your software now, and it should work flawlessly.

At the end of the day, messed up permissions can cause a lot of headaches, and may mess with your ability to install software. All you need to do is to follow the steps in the aforementioned methods and you’ll be able to install your software without any problems whatsoever.