autocad 2007 copy paste problem

hello,

i am at an interior design office i am having problem with copy paste in autocad 2007. on most of the machines

once we copy a part of drawing from a file to an other and paste in the desired file, the pasted objects are not what we copied, it paste objects from i don't know where, we changed the computers, opened the files, the same pasted data appear again, and each time a different one,

we keep pasting and undoing until it paste the things we want.

let's say i wanna copy a BED from dwg A to DWG B

when i paste in DWG B instead of the BED it pastes a Kitchen per example (no open file that have kitchen in it opened since a long time, and sometimes never opened)

we undo and paste again a bathroom come now, we keep doing this until we get the result we want, it's wasting our time.

Notes: files are opened on the network through shared folder

please if someone can help me with this. it didn't happen before , it's a new problem happening since 2 weeks maybe.

thank you.

Apart from a major defect, the only thing that occurs to me is a block definition that is already defined. Try purging the drawing and inserting the drawing.

the problem is happening on most of the computers, with different files, we tried to purge, but still happening.

we have a new pc with fresh autocad instalation , the same thing is happening, it's pasteing very old stuff we don't know where it's coming from