Nearly every video I try to play is "corrupt"

[ChristopheM99]

I have always used VLC on my computers with great pleasure. Recently, when viewing different kinds of video files on my girlfriends´ computer, I have some trouble. It seems that all files that are totally OK on a different computer are corrupt when played on this one. The message "file is corrupt, choose to repair" is displayed at the beginning:
1. when ignored, the file always stops playing at a certain point, near the middle of the video file.
2. when trying to restore the index with VLC, the reparation process stops at the same point.
I would like to stress that these files are totally ok on a different computer.
I have tried using different versions of VLC. First one used was 1.1.4, Second 2.0.3 for x86, since I am running windows 7 on a 64bit I also tried the experimental 64bit 2,0,2, the same problem occured.
The files were all basic .avi files.
Thanks

[Lotesdelere]

The problem must be within the files or something wrong on the computer. VLC just detects an invalid AVI header.
To be sure VLC is not at fault reset the VLC preferences and try again. If the problem still occurs then the problem comes from the computer. Googling for "shmedia" might give some usefull tips.

[Rogerick]

I posted this also in general section//- NOT Windows SPECIFIC > but if not here, many would miss this easy quick non-destructive fix.

Our family has desktop Macs and one Powerbook. Also two windows laptops, XP and Win7, and Win7 Desktop. Win machines are bare, dedicated purposed.
HANDY FOR TROUBLESHOOTING TESTS.

PROBLEM:
I found MANY movies from x264 to avi, suddenly had 'broken files', I also suspected corrupted download first.
This problem became untenable frequency, after upgrading to version 2 VLC.

New movies were broken, and needed repair to play - that played fine on other [virgin software] machines!
Movies computer viewed took much time to rebuild - like every time I tried to 'rewind' for something I missed- to replay in part or whole! Replay meant rebuilding again. Hitting back button, also rebuild again. Frustrating.
When viewing without interruption, movie played fine after 'fix'. But 'repair' required every time played.
--------========--------
SOLUTION:
In Preferences, I 'reset' my advanced preferences to original 'default'. THAT's IT!
-------------------------------------------------------------------------------------------------
> Now VLC no longer assumes most files are 'broken', and plays without interruption (except when I try to REVIEW MISSED SECONDS USING BACK BUTTON!
> Please give us back our FAST/unique to MACOSX adjustable time back button!)

CAUSE of Problem: I believe something I set up years ago, remaining in preferences as upgrades removed original necessity, caused this.
Still not sure exactly what, but two machines narrowed it to the input and codec section of preferences.

Resetting it to original default settings, easily fixed this problem for us, so I registered, and posted it here now, to share.