I’m regularly have to download some Excel files from the internet and it is quite annoying when it sometimes starts open an empty file like this:
It looks really confusing as it does not show you any errors or warnings (Excel thinks that it did what you wanted and all is OK? 😉 ). But actually this is protected view in action. Though what I’m really don’t understand where all the warning supposed to accompany this mode 🙂
So in case you want to open your Excel files downloaded from the internet you have to navigate to File > Options > Trust Center > Trust Center Settings > Protected View:
The problem is that when you try to open Excel file downloaded from your browser without saving it first you are subject to two restrictions at once (highlighted in yellow above): first your file is marked as downloaded from the Internet and second it is being placed somewhere in temporary Internet files which consider as potentially unsafe location. So just un-check these things and you will be able to open your Excel files downloaded from the internet without need to save them somewhere first. There will be some warning/prompt where you will be able to say open anyway and file opens just fine after this.