We have the Panels view 1250+ (2711P-B12C4A2) along with the SLC 5/05 (1747-L551) all set up with ethernet communications (ethernet switch).

1. RSLogix 500 software 7.00
2. RS Linx Classic for Factory Talk 2.52
3. Factory Talk View Studio 5.00

From what I see everything is configured for ethernet communications and the unit does operate properly. Every so often we get the pop up screen with the following message:

(red X with a circle) DF1:Failed to open COM5: as it may already be in use by another application.

3 lines of this

We clear it and it comes back later. It don't have anything else running, that I know of. How do we troubleshoot and find the cause? Any ideas?

Thanks in advance.

On the PanelView Plus...(I"ve Practically have the same setup here on my desk with a SLC 505 -L553)

Go to terminal settings: <enter>
Networks and Communications: <enter>
RsLinx Enterprise Communications: <enter>
Virtual backplane Should have (No Devices) If not remove device
and
Ethernet Should be tied to your PLC IP address

Hope this Helps

Very likely what happened is that you used the "Copy" button to copy the Shortcut and network schema from the Local to the Target tabs in RSLinx Enterprise.

That copies all the drivers and network nodes, not just the ones being used by the current application. That DF1 driver (probably connected to a USB/RS232 converter at COM5) got copied over and is just hanging out there, attempting to auto-configure to a nonexistent COM port on the terminal.

You should be able to delete it on-terminal, and next time you work on the application in FTView Studio, go directly to the RSLinx Enterprise "Target" tab and remove it from there.

I've also heard that you should delete Ethernet devices that won't exist in the target environment from the Target tab's configuration, so that the onboard RSLinx Enterprise won't waste resources attempting to browse and identify them.

If you are running to ap from rsview studio you need to make sure that rslinx is not running, this could be why you are getting the comm error

Thanks to all. Sounds like what Ken said is probably happening. We have used the USB/Serial Com port on other AB PLC's. We'll clear it out in the terminal itself as suggested.