I've been studying msgs on SharePort since I got my DIR-825 last month--been experiencing the same issues. I may have a PARTIAL fix.
Make of the following what you will:
DIR-825 Router Connected via Wireless
DIR-825 Hardware v A1
Firmware v 1.12NA
SharePort v 1.10 R1 SXUPTP Driver 3.3.4.0
Windows Vista (64-bit)
I, too, experienced connectivity to USB devices for a few hours to be followed by SharePort attempts to connect that result in devices seen, but not connected.
Out of curiosity, I logged into the router as Admin to inspect the logs; specifically, "Log Details".
Router Admin Application Interface:
"Status" Heading (Top Right)
"Logs" (Left Side)
Below "Log Options" is "Log Details"
To make for clean tests of starting and stopping SharePort, I "Cleared" the log and started SharePort (a Refresh of log would reveal the SharePort startup steps within the log).
The USB device CONNECTED after not being able to connect before with only a log clearing to explain it.
SharePort has been working for about 3 hours (NOT yet a conclusive test). I'll monitor over the next few days.
The same answer to the following questions is, "I don't know".
1) Did merely logging into the Router Admin Interface "fix" the USB problem?
2) Did clearing the log "fix" the USB problem?
3) Will the fix hold permanently?
4) Will this fix work again on my computer/router?
5) Will this fix work on your computer/router?
If nothing else, if this procedure works for you or again for me, it represents a substitute for rebooting the router.
That's something.
Note: I am not aware of any "log out" feature in the Router Admin Interface. I cleared ALL browser history and private inputs before closing the browser. I then waited an hour or so for the router to timeout the session (I don't know the router's timeout limit), confirming this by attempting a direct read via the browser by using a URL other than the main menu (http://192.168.0.1).
For example, if the session remains open after the browser is closed, one can open a browser and bypass the main page by using any specific page URL, say, like this one:
http://192.168.0.1/Status/Device_Info.shtml
My point is that I confirmed the Router Admin session was closed and the SharePort feature continued to work.
I'll follow-up if I experience any changes.