You can use transportable tablespaces, but you must put the tablespace in question in read only mode. If this is your production db, then you have a problem.
Normal export is possible while users are present.
alter tablespace x read only;
and then something like:
exp transport_tablespace=Y tablespaces=x
and after that the same in imp.exe.
Use EXP HELP=Y and IMP HELP=Y in your command prompt for the complete set of parameters.
PS: Don't forget to write-enable the source ts...
PSPS: To my knowledge, this question was already solved once. Please try to search the site before posting your question. It saves you the time of typing your story
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