No access once file is dragged & dropped

Ok, here's the issue:

I have hundreds of folders under "my documents", since it's the fastest place to access things. I have had problems in the past till now when I have created a file (of whatever) and needed to switch it to a new folder. So I open two windows & drag the existing file to its new location. Let's say the file is a FLASH MX creation (.fla). Once the file is "drug" to its new location, I double click it and it gives me an access error. If I go into FMX to open it directly, it says the file cannot open. The same is true with folders being opened in various programs. Once dragged to a new location, the folder becomes inaccessible. When trying to open a folder from a specific program, I get the same "accessibility error" i.e. "access is denied..." I have tried several things to no avail. PLEASE, if someone knows, help. I'm gonna go postal!