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USB to RS-232 adapter = unknown device

Last response: in Windows XP
September 22, 2011 8:57:04 PM

Got a new (cheap) USB to RS-232 adapter - CD that came with it was blank.
Only info in device properties is:

Can anybody help me?


September 23, 2011 2:38:08 AM

Have you got a Brand? Your OS and version would be good too.
September 23, 2011 7:00:55 PM

Well I thought I would just write off my big expense, but this is what I have.

Think both that I bought have PL-2303 chips.
Where I bought them - 59c Importer520

And bought for 30c this
...... Both had CDs , one was blank. Downloaded from net a new driver, still get
"cannot start (code 10) on one and "unknown device" on other. Win XP and Win 7 on two machines.


starzty said:
Have you got a Brand? Your OS and version would be good too.

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September 23, 2011 9:27:38 PM

Looks like the URLs didn't survive Tom's filters, but if you google B000K02UP8 , it should come up with a picture ad of the device with a (Prolific PL2303HX Chipset)

My computers are HP laptop and homemade, both running XP Pro ver 5.1 SP3

Also tried the adapters in a machine running Win 7 ver 7000? beta - same end result.

September 23, 2011 9:28:20 PM

What driver did you try? the CH341SER? I've actually used one of those in Linux, which I'm sure isn't even a little helpful

It's ok, the links behaved for me
September 23, 2011 10:40:18 PM

Have not seen " hl-340" or (ch341ser.sys) anywhere in the testing or documentation

They seem to be made by
Prolific Technology Inc. PL-2303 (Chip Rev H, HX, X) USB to Serial Adapter
Windows, Driver v1.4.17


Best solution

September 23, 2011 10:51:30 PM

Worst case scenario it continues not to work
September 23, 2011 11:03:35 PM

Best answer selected by edhiker.
a b \ Driver
October 26, 2011 7:43:43 PM

This topic has been closed by Area51reopened