Drive partition is now locked

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Do not know how it happened but have a Mac Mini late 2009 Snow Leopard, one user only.

2 Partitions, one for OS etc., one for My Documents.

The 2nd partition now has a lock on the desktop icon. Permissions say custom. Can unlock in get info window but can not change from custom.

Can not open 2nd partition.

Should I try PermissionsReset.app or ?

Thanks in advance for suggestions!

 

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The app worked, still no cliu on how it came to happen in the first place