Wtashby,
Don't know where in the process of suggestions thathavebeen made. If the "original" site is still available, is EP4 the only option on your admin panel that is not accessible at this point? Information in your admin's catalog is the same as on the store's side? (Ie, the configure.php files effectively match the same directories and database? This may become more evident when the above install suggested by chadderuski is performed and the files reviewed. (These could be different than expected if it was thought thaat they were saved but the write permissions were not changed to allow writing before trying to save.)
I realize that there seems to be a problem, but there have been several that have installed this to 1.5.3 and having equivalent settings thathavent had the same problem.the thingis to find the cause and perhaps incorporate some sort of solution up front to more clearly explain what is going on and possibly a solution.
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