Yellow exclamation mark next to my Prolific USB in device manager

Hello NrBolton1,

Thank you for posting.  I've looked in to your problem and found some very recent updates for you hardware.  I've included the link below.

http://www.prolific.com.tw/eng/downloads.asp?ID=31

I would also highly recommend that you take a look at the "FAQ Webpage" link that's contained on the site.

Please let me know if this helps you.

---

Zack
Microsoft Answers Support Engineer Visit our Microsoft Answers Feedback Forum and let us know what you think.

Hi

Many thanks for your reply.  However, that's the link that I used to find the latest version of the driver.
I've read in other blogs that "The device cannot be started (code 10)" could be a conflict with a sound driver? I've uninstalled and reinstalled sound drivers but this hasn't worked.

The USB>serial convertor worked before I had to reinstall windows, so I know it's not faulty.

Any more ideas would be great.
Thanks

Hi nrbolton1,

Thanks for the responses to answers.microsoft.com

From the release notes on the driver
PL-2303 Driver Setup Installer, Prolific Edition
Setup Installer Revision Note History

"Release Notes:
---------------
PL2303 Driver Installer v1.0.3.11
  Changes from Installer v1.0.2.5:
    . Fixed problem when running installer in Windows Server 2003.
    . No driver change from previous installer.
 Windows 98/ME Driver: v2.0.0.19
 Windows 2k/XP/Server2003: v2.0.5.111
 Windows Vista/Server2008: 3.3.3.114"

It appears in Vista there were no changes to the driver from the previous driver.  You may want to rollback to previous version on the device driver and see if that resolves the issue.

Right click the device / select DISABLE / then Right Click it again and select Properties -to try to bypass the CANNOT START error.  You should be able to rollback to previous version on the driver from under the Driver tab.

Please let us know if this resolves the issue or if further assistance is needed.

If it does not resolve you may consider choosing a restore point for your desktop from a time prior to the error occurring.

Here is information about a restore:

http://support.microsoft.com/kb/959063

Remember all data and changes made on your system after the selected restore point will be lost. 

---

Debbie
Microsoft Answers Support Engineer
Visit our Microsoft Answers Feedback Forum and let us know what you think.

read this: http://support.microsoft.com/?kbid=310575

its for xp but same principals should apply for vista

Remove and reinstall all USB controllers To remove and reinstall all USB controllers, follow these steps:

1. Click Start , click Run , type sysdm.cpl in the Open box, and then click OK .
2. Click the Hardware tab.
3. Click the Device Manager button.
4. Expand Universal Serial Bus controllers .
5. Right-click every device under the Universal Serial Bus controllers node, and then click Uninstall to remove them one at a time.
6. Restart the computer, and then reinstall the USB controllers.
7. Plug in the removable USB storage device, and then test to make sure that the issue is resolved.

Hi

I've tried the older and newer version of the driver.  The option to roll back isnt available in properties.

The computer went through a full destructive recovery, so i can't restore the computer as it's not worked since the recovery and dates before this are unavailable in system restore

Any other ideas?
Thanks

Hi thanks for this suggestion, however removing and reinstalling all USB controllers has not solved the problem.
I still have the yellow exclamation mark next to the USB to serial device (COM4) in device manager.
It still says The device cannot be started (code 10) in properties.

Any more ideas?!
Thanks

Hi nrbolton1,

You mentioned that the Prolific PL2303  software worked before you reinstalled Windows.  Were you using the same version of Vista 64bit when the device was working?

Are you able to find a driver for this device on Windows Update?
http://windowsupdate.microsoft.com

You can check Windows Update anytime to see if it has found new drivers for your hardware. Then, you can install them if you choose. Here's how:

1.  Open Windows Update by clicking the Start button , clicking All Programs, and then clicking Windows Update.‌  If you are prompted for an administrator password or confirmation, type the password or provide confirmation.

 2.  In the left pane, click Check for updates.

 3.  To see if updated drivers are available, click View available updates. Windows Update will list any updated drivers that are available for devices installed in your computer.

 4.  If updates are available, click the driver that you want to install, and then click Install.  If you are prompted for an administrator password or confirmation, type the password or provide confirmation

Is your pc up-to-date with Windows updates?

Have you tried to un-install the Prolific PL2303  device in Device Manger and checked whether Windows installs the driver on it's own once you reboot?

---

Kavita M
Microsoft Answers Support Engineer
Visit Microsoft Answers Feedback Forum
and let us know what you think.

Hi

Yes it was the same version of Vista 64 Bit before.

The PC is uptodate with updates.

Windows doesn't instaill the driver on its it once I reboot.

I'm getting desperate!!
Thanks

nrbolton1,
Here are a couple of articles that might apply to your issue.  If these do not help you resolve the issue, the next step is to do a clean install of Vista, even though this is a new install.

http://support.microsoft.com/kb/933442

http://support.microsoft.com/kb/329184

Let us know if any of these things help resolve your issue.

Thanks,

---

Gloria
Microsoft Answers Support Engineer
Visit our Microsoft Answers Feedback Forum and let us know what you think.

Thanks for the suggestions, however neither of those articles were able to solve the problem.

I'd rather not do a clean install of Vista, as I've just done that and that was when the device stopped working.

Any more ideas?
Thanks