downloads not showing up in computer

If the download is still in the download queue then it means it's not done yet so it's normal not to be in the download directory ? Are you sure the download finished? If the download appears in Finished Downloads, it means only a chunk of it its done, not the whole file.
Also, check this question :
https://answers.launchpad.net/dcplusplus/+question/28603

I found out what the problem was but no reason as to why it happend. I ran a complete search and found the files.

On DC++ my downloads directory is:
"C:\Program Files\DC++\Downloads"

But where they actually ended up:
"C:\Users\[my username]\AppData\Local\Virtual Store\Program Files\DC++\Downloads"

I have no idea why it referenced there.... i've never chose to set it there in the first place. One hypothesis i have is that turning UAC on and off my make it refer here. Also I ran DC++ as administrator and chose my download directory to what i already had, but started again by clicking My Computer and so forth. I downloaded a file afterwards and it ended up in my directory.

I'm confused.

I think Vista is guilty. It may have interfered. Can't help you much , because I never tested on Vista and I don't know how the operating system works. Perhaps someone else can point out if this is a bug or Vista's fault

No its no UAC itself, its the matter of running DC++ as admin or as an ordinary user : http://forums.microsoft.com/MSDN/ShowPost.aspx?PostID=724050&SiteID=1
It answers those many support issues where users can't find their downloads...
So TempD (and all Vista users) you'd better to set your download and unfinished folder to somewhere outside Program Files...

I would recommend that we change DC++ to default to a different directory than the program path. On *nix, we point to $HOME to store user data. I suggest a similar change be made to DC++ (e.g. using %HOMEPATH%) so that program data and user data are separated.

Yeah, actually this can be done already by changing dcppboot.xml appropriately - what's been holding me off so far is the upgrade path that needs to be worked out...also, on windows there are several locations that make uhm...sense...there's application data, my documents, local application data, %HOMEPATH% (which is not where windows apps generally should store things)...
I'm guessing that settings and the default download location should be in different places as well...

Well, that's good to hear it's being considered. Yeah, I'm not sure where exactly to put it (%HOMEPATH% was just a guess), just that it should be done. :)

Anyway, you don't really need to change settings and default download location, you just need to update Util::initialize() to change configPath to an appropriate directory. This will take care of it everywhere since the settings use that path.

well, the point is that on windows there are multiple homes, one for user-visible stuff (my documents) and one for scary config files (application data or local application data) so putting downloads in the appdata kind of sucks, and putting config files in my documents sucks too....

At some point we'll flip the default to save to "my documents" somewhere, but the upgrade path needs to be considered...

| I have no idea why it referenced there.... i've never chose to set it there in the first place. One hypothesis i
| have is that turning UAC on and off my make it refer here.

Windows Vista's file and registry virtualization is covered at http://technet.microsoft.com/en-us/magazine/cc138019.aspx
This is why your files are redirected.

| At some point we'll flip the default to save to "my documents" somewhere,
| but the upgrade path needs to be considered...

I'd recommend %USERPROFILE%\Downloads which is an already existing directory in Vista and defaults to C:\Users\Username\Downloads (instead of C:\Users\Username\Documents\Download). Actually I should verify what %USERPROFILE% is under Windows XP.

In XP . . .
C:\>cd %USERPROFILE%
C:\Documents and Settings\Administrator>
:)