An eml file is usually formatted like this (or real close to this):
Subject: Re: Sample EML
From: RS <E-Mail Address>
Reply-To: <E-Mail Address>
Date: 5/2/2014 7:17 PM
To: Mailing List <E-Mail Address>
User-Agent: (edited for post)
Text of message
In WINDOWS LIVE MAIL, if I recall correctly the text is encrypted. I looked at WINDOWS LIVE MAIL some time back. For other programs other than WINDOWS LIVE MAIL, the EML files are normally plain text, which can be opened with any TEXT EDITOR.
No offense, but I experimented with AVG previously, and in my opinion, it's on the bottom of the list of programs a person would want to use. I've been virus free since the fall of 1995. I tried two programs, Norton AV and McAfee. McAfee found half of what Norton did. I saved the viruses to floppies (showing my age). Later, I tried to scan the floppy with AVG, and it found only about 12 out of 600. I've tested AVG quite a few times since then, and the results where the same.
Since then, I've abandoned Norton. I now use AVAST, and it's saved my bacon quite a few times. I suggest that you use AVAST instead of AVG.
Presuming that AVG is your choice, you want to stay with it, and you trust it, and that "28337874-000001B5.eml" is the actual file name, then:
1. Open a Admin level command prompt.
2. Go to the folder where "28337874-000001B5.eml" is at.
3. Enter the command (no quotes): "type 28337874-000001B5.eml | more"
4. Yes, at the end is a space, vertical bar, space and the word more.
The above will display the file, a screen (command prompt screen) full at a time, and display "-- More --". Press the space bar to see another screen full.
However, although the above will allow you to see the above, without opening it in a program, I recommend that you just delete it, securely. Go to fileshredder.org, download it, and install it. Then drag and drop the file into it, and use the DoD method to securely erase all tracks of the file (again I don't trust AVG).
Best of Luck.