Failed to load resource: net::ERR_CONTENT_LENGTH_MISMATCH

This error is definite mismatch between the data that is advertised in the HTTP Headers and the data transferred over the wire.

It could come from the following:

1. Server: If a server has a bug with certain modules that changes the content but don't update the content-length in the header or just doesn't work properly. It was the case for the Node HTTP Proxy at some point (see here)

2. Proxy: Any proxy between you and your server could be modifying the request and not update the content-length header.

As far as I know, I haven't see those problem in IIS but mostly with custom written code.

Let me know if that helps.

It could be even caused by your ad blocker.

Try to disable it or adding an exception for the domain from which the images come from.

Docker + NGINX

In my situation, the problem was nginx docker container disk space. I had 10GB of logs and when I reduce this amount it works.

Step by step (for rookies/newbies)

1. Enter in your container: docker exec -it <container_id> bash

2. Go to your logs, for example: cd /var/log/nginx.

3. [optional] Show file size: ls -lh for individual file size or du -h for folder size.

4. Empty file(s) with > file_name.

5. It works!.

For advanced developers/sysadmins

Empty your nginx log with > file_name or similar.

Hope it helps