IQFeed-streaming-data-failure

Uninstalling and reinstalling won't likely change anything. Maybe reboot Windows?

Windows Reboot has been done several times.

I just tried to update a streaming chart and got this error message:

System.NullReferenceException: Object reference not set to an instance of an object.
at WealthLab.IQFeed.IQFeedStreaming.SubscribeTo(String symbol)
at WealthLab.Data.StreamingProviderBase.Subscribe(String symbol, IStreamingConsumer consumer)
at WealthLab.ChartWPF.CoreChart.ReflectSystem(BarHistory init)
at WealthLab.ChartWPF.CoreChart.AssignBars(BarHistory value, Boolean setOffsetZero, Boolean force, Boolean calledFromStreaming)
at WealthLab.ChartWPF.CoreChart.set_Bars(BarHistory value)
at WealthLab.ChartWPF.Chart.ForgotGetter(Boolean issetup, DataSet b)
at System.Threading.Tasks.Task.<>c.<ThrowAsync>b__128_0(Object state)
at System.Windows.Threading.ExceptionWrapper.InternalRealCall(Delegate callback, Object args, Int32 numArgs)
at System.Windows.Threading.ExceptionWrapper.TryCatchWhen(Object source, Delegate callback, Object args, Int32 numArgs, Delegate catchHandler)

When I use the Data Manager - Historical Provider - Historical Data Loading Testbed for symbol F I get the following error message:
"Error: Error reading IQFundamentals.csv. Make sure the file is closed.
Index was outside the bounds of the array."

the IQFundamentasl.csv file has a size of 3,465 KB, but when I open the file in Excel, I see no data.

Should I open the file in Excel and then save it even though there is no data shown in the spreadsheet?

I think this a networking problem and needs to be troubleshooted from the IQFeed and OS side, not the WL8 side. Open up some of the IQFeed Diagnostics and tells us about port# connections involving IQFeed, WL8, and IQconnect. What is the IQFeed Diagnostics log telling you about failed connections?

Was there a Windows update that changed firewall settings?

These are some of my results, and my IQFeed connections are all working normally.

I set the IQFeed Diagnostics Utility logging tab to log All Requests and all Errors.
After opening Wealthlab and opening a streaming chart I checked the IQFeed Diagnostics log and and found no errors but did see Client Stats for WealthLat8.exe.
the IQFeed Diagnostics Net Stat tab show TCP connections established for WealthLab8.exe. and shows no errors for WealthLab8.exe.

If I test Symbol F in the IQConnect tab The test Log tab shows connections success - no failures. The streaming Quote tab show quotes coming in.

I'm still suspicious of the "Error Reading IQFundamentals.csv File" complaint in Wealthlab Data Manager Historical Providers. I suspect that failure reading that file prevents WealthLab from requesting updates from IQFeed.

QUOTE:
If I test Symbol F in the IQConnect tab The test Log tab shows connections success - no failures. The streaming Quote tab show quotes coming in.

Okay, so the network connections are okay.

QUOTE:
I'm still suspicious of the "Error Reading IQFundamentals.csv File" complaint in Wealthlab Data Manager Historical Providers.

I get that error occasionally with WL6, but not so much with WL8. The IQFeed client writes that *.csv file and the WL8 IQFeed provider reads it. When the provider tries to read it at the same time the IQFeed client is trying to write it, you receive that error. That can happen when there's lots of load on the OS. But this has more to do with IQFeed fundamentals provided to the IQFeed provider. It has nothing to do with streaming price data, which is the focus of your problem.

I would try temporarily switching to a different price streaming provider to see if that works. Afterwards, I would switch streaming providers back to IQFeed to see if that now works.

QUOTE:
I replaced the IQFundamentals.csv File with one from a backup file. WealthLab data updates worked normally after replacing the file.

The IQFeed client creates that file. Perhaps the file was locked by the OS such that neither the IQFeed client (the "writer") or the IQFeed provider (the "reader") had access. I'm not sure how such a deadlock condition would occur that would hang the system.

I don't like the way DTN creates such an IQFundamentals.csv file in the first place. I would have used some kind of message passing to move that data between processes.

The IQFeed Provider caches the fundamental data using a temporary Streaming subscription when requesting historical data.

Since there's only one record per symbol and no "history" you can delete that file at any time (you just need to update all your data to recover it). Anyway, we'll work on detecting and doing something about the error condition.

Cone,
I had the file in the IQFeed folder, but it was blank. I replaced it with the file from the prior day's backup. If I understand you, I could have deleted the file and the system would have recreated it.
Thanks.

QUOTE:
we'll work on detecting and doing something about the error condition.

If you have control of both the "reader" and "writer" thread, then the simple .NET solution is to store the fundamental data in a thread-safe datatype. That way, .NET manages the contingency and you're not using the disk.

I see this error more with WL6 than WL8 when the OS is busy with I/O.

QUOTE:
I could have deleted the file and the system would have recreated it.

Yes. It creates (or replaces) the records as you request historical data from IQFeed.