Reducing Omega's folder !?!?!?

["S F" <singfr@xxxxxxxxxxx>]

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I'm using TS 4.0. My Omega’s folder has recently reached 1 Gb. I’ve backuped 
all stocks/futures/indexes/mutual funds by means of the Copy-out function 
and also by doing a copy of the whole folder. Now I’d like to reduce the 
folder as much I can. I’ve tried to delete a single stock and 6 expired 
future symbols from Portfolio BUT the folder seems not to decrease.
What can I do?

Thanks
Fred S.
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