USB Modem Issues - Help!

It’s like this—I grabbed my sister's USB modem, though I haven't bothered to check the specific model or specs. Every time I plug it into my laptop, it attempts to trigger some installation process before throwing an error stating "the system cannot find the path specified"—all while making that distinct disconnection sound, despite the device being physically seated. I've tested all three ports on my machine with zero success. It behaves identically on my girlfriend's laptop, too. The hardware itself is functional—my sister uses it without issue and a friend confirmed it works perfectly on his rig—so the problem is isolated to my devices. I desperately need this connection working 🙂 perhaps someone here can identify the underlying issue 😁 Thanks.

??? Is it a USB Wi-Fi adapter or some kind of 3G dongle... what kind of thing is it exactly? Does it have any labels on it? And does everyone else get the same connection when they're standing in the same spot you are?

Honestly... I have no idea what's going on here. 😁 It's a standard USB stick—I found online that the model is a "Motorola Razr"... works perfectly fine for everyone else; my sister and brother can use it at home without issue. I brought the stick with me while visiting my girlfriend for a few days, but now, on both my laptop and hers, I keep getting the same error: "The system cannot find the path specified." Initially, I thought the stick itself was broken. I even went to a Verizon store here in San Francisco, where they gave me some vague nonsense about the stick being faulty and suggested I take it to a mobile repair shop to check if a wire is loose or something. 😁 So, I went to the repair guy, but he didn't even bother opening it—he just told me to toss it, pull the card out, and buy a new one for $60. I didn't throw it away, though, because I know it works; I tested it on a friend's laptop here in San Francisco, and everything installed and ran perfectly. Clearly, the USB isn't the problem. :P I've been messing around with settings and checked Device Manager to see what happens when I plug it in... this popped up: 😁 another "USB Mass storage device" appeared, but with a yellow warning triangle. When I click it, I get: "Currently, this hardware device is not connected to the computer. (Code 45)

To fix this problem, reconnect this hardware device to the computer." I realized the stick keeps disconnecting after a few seconds—every time I plug it in, the installation starts, and then it just drops. :P I genuinely don't know what the issue is; it’s happening on both laptops. :/

I've also Googled various solutions, but nothing has worked so far..