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Cannot Open Com Port Error

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Hi,

I've just finished a clean install of my fs-computer, and tried to reinstall my FSLabs drivers, but get an error: cannot open com port.

I've checked the correct com port in the systems settings, and tried to CPFlight test software, which works fine. But when I run FS I get this error.

What could be the problem?

Thomas

Thomas,

can you make sure that the test software is NOT running, when you run FS? Serial ports are consumed by ONE application at a time, so any app/utility that has it open will forbid other applications (hence FS) to open them too.

  • Author

Lefteris,

Thanks for the quick reply.

Just made a reboot, and clean start of FS, same problem...

Hi Thomas-

can you check the .ini file in the <FSX>\FSLabs folder? Was it a different one before you reinstalled? If yes, perhaps you want to set it manually in the .ini settings.

  • Author

Lefteris,

Problem solved!

Unplugged USB from computer, put it in a different one, winxp asked for driver reinstall, got assigned new com port, and now it works great...

  • 2 weeks later...

Hi,

I've just finished a clean install of my fs-computer, and tried to reinstall my FSLabs drivers, but get an error: cannot open com port.

I've checked the correct com port in the systems settings, and tried to CPFlight test software, which works fine. But when I run FS I get this error.

What could be the problem?

Thomas

Dear Lefteris,

exactly the same problem after reinstall here.

But choosing another port does not solve my problem.

Best from Vienna

Georg

Georg-

same question to you then (which wasn't answered by Thomas before) :

can you check the .ini file in the <FSX>\FSLabs folder? Was it a different one before you reinstalled? If yes, perhaps you want to set it manually in the .ini settings.

Georg-

same question to you then (which wasn't answered by Thomas before) :

can you check the .ini file in the <FSX>\FSLabs folder? Was it a different one before you reinstalled? If yes, perhaps you want to set it manually in the .ini settings.

Dear Lefteris,

If you mean that the COM-Port is another one: Yes, I am using a new motherboard (new CPU and additional HD where FS is reinstalled). Therefore all USB-Ports are new ones and different than before. Tried different of the app. 14 USB-ports without success.

Deinstalled and installed MCP and fslabs-drivers.

MCP (FS-COM)is working as should be. And yes I don't have another tool running using the relevant COM-port /as far as obviously).

Because of reinstall the .ini-file is also a "new" one. I even set the COM-port-number manually, but without being recognised by the driver.

Georg

Dear Georg-

I am sorry for your troubles. At the moment, I cannot offer any more help, other than to recommend that you use the default CPFlight test utility (if I remember correctly, there is one), to find out which COM port your USB driver emulates. Once that's found, you can set it in the.ini file and it should function properly.

Best regards,

Dear Georg-

I am sorry for your troubles. At the moment, I cannot offer any more help, other than to recommend that you use the default CPFlight test utility (if I remember correctly, there is one), to find out which COM port your USB driver emulates. Once that's found, you can set it in the.ini file and it should function properly.

Best regards,

That was exactly what I did and what does not work.

Even if the CPFlight test is ok and the port is entered manually into the .ini.

Any concerns about reinstall and hidden fragments of the former installation of fslabs driver?

Otherwise I may try another reinstall (FS9.1, PMDG and MCP/fslabs in another pertition (there is one empty left...)

Georg

Georg-

did you do the installation in the proper order? (737NG first, all updates next, ensuring that 800/900 is up-to-date, then the drivers?)

I have installed 737NG 600/700 V 1.3B (box), then 737 800/900 V1.1 (box), then the model update-patch.

It is strange, cause before everything worked flawless.

What I don't understand is, that Thomas' PC was asking for reinstall of drivers by changing the plug.

Mine is accepting and registring another plug for MCP without additional driver install/with the existing installation.

And in any case the CPFlight test utility say ok.

Dealing with the ides of setting up everything competely new. But will have to travel through/under the ash-cloud first the next days...

Georg

  • 2 weeks later...

Dear Lefteris,

OK, did a complete delete and reinstall of FS 9.1, PMDG (737NG 600/700 V 1.3B (box), then 737 800/900 V1.1 (box), then the model update-patch), CPFlight and FSLabs Driver (even I deleted those in system32\drivers\ftser2k.sys and system32\ftserui2.dll).

After that WinXP is not asking for new drivers if connecting the MCP, but applying some drivers onboard identifying the MCP as "USB Serial Port (COM 11)" and not especially as "CPflight serial adapter (COM 11)" as promised by the CPFlight readme.

Therefore I updated the USB-driver with the newest ones of CPFlight.

But no success: The MCP is recognized perfectly by FS_COM at port 11 but not by fslabs application (even if port 11 is set manually in the ini-file.

Any idea?

Or do I have to switch to FSX and wait for PMDGs new baby?

Best from Vienna

Georg

Dear Lefteris,

OK, did a complete delete and reinstall of FS 9.1, PMDG (737NG 600/700 V 1.3B (box), then 737 800/900 V1.1 (box), then the model update-patch), CPFlight and FSLabs Driver (even I deleted those in system32\drivers\ftser2k.sys and system32\ftserui2.dll).

After that WinXP is not asking for new drivers if connecting the MCP, but applying some drivers onboard identifying the MCP as "USB Serial Port (COM 11)" and not especially as "CPflight serial adapter (COM 11)" as promised by the CPFlight readme.

Therefore I updated the USB-driver with the newest ones of CPFlight.

But no success: The MCP is recognized perfectly by FS_COM at port 11 but not by fslabs application (even if port 11 is set manually in the ini-file.

Any idea?

Or do I have to switch to FSX and wait for PMDGs new baby?

Best from Vienna

Georg

Georg-

any COM port above COM9 will not be recognized by the driver (serial port software limitation). You need to delete the older COM ports (which are unused) - don't worry, they're emulated, so it's reasonable to do, then delete the USB port driver and let it reinstall. If all goes well, you'll now have a port less than 9.

(I had this happen to me too, when I was testing - I was plugging / unplugging constantly, so Windows kept creating more ports until this started happening).

Let me know if that helps!

Thanks a lot! This was it.

Deleted the inactive COM-ports, reinstalled the CPFlight and fslabs-drivers, everything works as it should.

One of the side-aspects of flightsimming is you have lifelong learning about your PC and OS :-).

Best from Vienna

Georg

Great news!

I am happy you are now back to your normal simming :).

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