Error when installing Chrome extension from file: CRX_HEADER_INVALID

Question

I am trying to install extension on Google Chrome and I get this error when I drag and drop a .crx file onto Extensions page: Package is invalid: CRX_HEADER_INVALID.

How can I install it?

Answer 1

Change file type .crx to .zip and extract zip file to a folder.

Open the extensions page in Chrome or navigate to “chrome://extensions” from the address bar.

Check the “Developer mode” to enable the developer mode.

Click “Load unpacked” and select folder of extracted zip file;

Answer 2

This problem was reported on Mar 13, 2019 and closed as an intended behavior.

According to Chrome Enterprise release notes:

• All extensions must be packaged with CRX3 format in Chrome 75
  Starting with Chrome 75, all force-installed extensions will need to be packaged in the CRX3 format. Privately hosted extensions that were packaged using a custom script or a version of Chrome prior to Chrome 64.0.3242.0 must be repackaged. If your organization is force-installing privately hosted extensions packaged in CRX2 format and you don’t repackage them, they’ll stop updating in Chrome 75. And, new installations of the extension will fail. See ExtensionAllowInsecureUpdates.

However, it seems like in Chrome 73 Google forced this change for new installations already and introduced a policy option for updates only.

---

So, after unpacking extension in an old format (as described in another answer) you could pack it back with your current Chrome version and then install it as usual. This way you won't have to always keep that extension unpacked somewhere.