Can copy from but not too directory on External HD

[EasyObserver]

HI...first time poster so I'll try not to be too confusing. I have an external TB HD and recently been having problems copying to a particular directory. I can copy FROM this directory with not too much of a problem. What happens is, when I try to copy to it from my CPU or CD/DVD drives, it starts out great for about 6 seconds...then a 30 second transfer suddenly turns into a 30 minute transfer. Also...last night I copied (painfully slowly) 4 files to this directory, let Avast run a virus check overnight and it said it couldn't read those 4 particular files because it couldn't read the source file, but didn't report any viruses. Did a Chkdsk today (Alllllll day), and it didn't report any bad sectors or anything, but when I looked at the report there were numerous "orphaned files", "Insufficient disk space to recover lost data" (there's 800gig still free??), "read failures"...etc...etc. Both drives, my C: and External (E:) are NTFS format. I can copy to and from all other directories on the External without a problem.

Any help would be greatly, greatly appreciated.

[Dalo Harkin]

This normally happens when the files are extremely big or you do not have write access to the specific folder.

what exactly are you trying to move?

[EasyObserver]

It was larger files..avi files. But it doesn't matter at this point, I have a new problem, I was formatting this HDD and the cat decided to step on the switch for the power bar, now the computer doesn't read that it's even there. Already started a thread concerning this problem.

[Dalo Harkin]

Have you gone to Control Panel>admin tools>disk management - is the drive in there?