How to Fix Error ‘7zip Cannot Open File as Archive’ When Opening Archive Files

The “Cannot open file as archive” error in 7-Zip appears right after you try to extract a file that is damaged or incomplete, usually without any extra details. This message means 7-Zip cannot recognize the file as a proper archive because important information is missing or broken.

The most common reason for this error is a failed or interrupted download or file transfer. Sometimes, it can also happen if you have an incomplete split archive, are using an unsupported file type, or the archive is corrupted inside.

Before you proceed with the methods below, ensure that the file you are trying to open is fully downloaded and not incomplete. Sometimes, archiving errors happen because the file has not downloaded correctly. Consider using a download manager instead of downloading directly through your web browser to prevent download interruptions.

1. Change the Default Program to Open Archives

Very often, this issue arises when the wrong 7zip executable opens the archive by default. When you double-click or select “Open,” the system uses the default program associated with that file type. If it is set to 7zG (GUI), you may encounter the error. To fix this, you must update the default to 7zFM.exe, the proper File Manager for opening archives.

1. Open your browser and download the Default Programs Editor software. After downloading, double-click the executable to launch the application.

   

2. Click on the File Type Settings option. This allows you to edit how different file types are handled.

   

3. Select the Context Menu option, which lets you manage both the default program and right-click menu settings for file types.

   

4. In the list, search for the file extension, such as .7z or .zip. Select your desired extension, then click Next.
   Note: Use this step for any archive file extension you are experiencing issues with.

   

5. Here, you can add multiple programs to the context menu or set the default via the Open command. Select Open and click Edit Selected Command.

   

6. Change the executable from 7zG (GUI) to 7zFM (File Manager). This ensures that double-clicking the archive opens it correctly with the File Manager.

   

7. Once the settings are updated, click Save Context Menu to apply your changes. Your archives should now open properly with a double-click.

2. Use an Alternative Program to Open the Archive File

Sometimes, the issue may lie within the 7zip program itself. To determine whether the archive is truly corrupted or if 7zip is malfunctioning, it’s helpful to use another reputable program such as WinRAR. This step not only helps you troubleshoot but may allow you to access your files directly.

1. Open your browser and navigate to the WinRAR official site to download it. Install the program by following the on-screen instructions.
2. Right-click on the archive file. In the context menu, you’ll find options from WinRAR. You can try to open the archive, or extract its contents using WinRAR.

   

3. If the file still does not open, consider using WinRAR’s repair feature, as explained in the next section.

3. Repair a Corrupt Zip Archive

If your archive is corrupted, using a dedicated repair tool can often restore its contents. WinRAR, for example, includes an effective archive repair function.

1. Open the WinRAR application by double-clicking its shortcut or searching for it via Windows search.
   Note: If WinRAR is not yet installed, simply download and install it using the official website.
2. Navigate to the location of your archive. Select the file and click the Repair icon in WinRAR’s toolbar.
   Note: Alternatively, the Repair Archive option is available in the Tools menu.

   

3. WinRAR will prompt you to select whether to treat the corrupt file as a Zip or RAR. You can specify a destination folder for the repaired archive. Make your selections and click OK.

   

4. WinRAR will attempt to repair the archive and save it to your designated location. Try opening the repaired file to see if the issue is resolved.