Media not always playing

Dear All,

I am currently testing the Media server to determine if it will fit into our organisation.  I am also a complete newbie using both Flash Pro and Media Server.

As part of trying to learn more about the system I did the various online tutorials and was able to get them to work on the server, with an internet browser and Flash.  I then took some of our current videos and converted them to mp4, flv & f4v, as our media is wmv.  I placed these files in a sub-folder of the "C:\Program Files\Adobe\Adobe Media Server 5\applications\vod\media" folder.

In Flash CS6 Pro I created a flash file with the FLV player (as shown in the tutorial). When I used the RTMP path "rmtp://localhost/vod" and the first file name "NewIntroduction" the video played perfectly.  I completed the exact same procedure but used the file "EffectiveStationeryCP" the video would not play in either Flash or a browser.  If I point directly to the file using the file path, the video does play. In Flash I get the following errors, based on what I try:

"The video player is in the connection error state. It enters this state when a video stream attempted to load but was unsuccessful. There are two possible reasons for the error: no connection to the server or the stream was not found."

or

"NetStream.Play.StreamNotFound : Adobe Flash tried to play a live or recorded stream that does not exist. Source can't be found"

NewIntroduction is 14MB & EffectiveStationeryCP is 26MB. My thought is that perhaps there is size limitation on these. Some of the test video files are as big as 500MB.

I have spend the last 2 days seeking an answer and what ever I have tried has not worked. Any ideas as to what the problem could be?

Thanks