There is no TP-LINK driver for T4U to run on Windows 10.
It is plug and play on Windows 10 as the system itself has the built-in driver.

M Diamond wrote

There is no TP-LINK driver for T4U to run on Windows 10.
It is plug and play on Windows 10 as the system itself has the built-in driver.

Yes I see that.

The speed question was related to the driver that Windows uses and other peoples experience with the same adapter.

EDIT:

It seems that Windows 10's driver for the RT8812AU chip is part the problem, this in turn probably leads back to Realtek. We'll just have to play the waiting game and see if a better driver gets released instead of the ones Microsoft use.

Even the most recent driver on the website is almost 2 years old contrary to what the website states, that and the distinct lack of drivers on the realtek site is annoying.

I did send a query to TP-Link regarding the driver (for win 7/8) including dates/revisions, never heard anything back, cheers TP-Link.

I just got one of these. I have a Mac that only has built in wireless N so I bought this to upgrade it to AC since my Archer D9 ADSL2 wireless router is AC and my iPad and iPhone are AC. First there were no Mac drivers on the CD so I finally found them as a download. All installed OK and I found it connected better using the WPS buttons on the router and the T4U. So I connected to the Router at 5Ghz but the WPS tab on the Wireless Utility only shows the 2.4Ghz. There doesn't seem to be any way to switch the T4U into 5Ghz like you can on a router. I rang their Tech Support but weren't much help. Pretty sure they didn't understand what I was asking. Really two things. Don't know if I've overridden the built in N with the dongle's AC or how to switch the dongle to 5Ghz. Certainly testing the Wifi speed from Mac to router is faster. From 162 Mbps to 216/246 Mbps but if I could change it to 5Ghz it might be faster still. Documentation is lousy even reading the Windows install doesn't help.