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NxCore Access and API Frequently Asked Questions

Have a unique problem? Check the forums for an answer or post your question there. If you need immediate help please contact NxCore support at or call 847-501-4787. You can also use instant messaging application built into NxCore Access to contact tech support.

General Questions

I just installed NxCore Access, how do I get real time data now!?

NxCore’s advanced technology monitors every data packet transmitted to each customer. If a packet is not received by the machine running NxCore Access, the NxCore servers will automatically resend the packet. This technology ensures NxCore customers receive a complete dataset each day, with each machine receiving the exact same data down to the byte. This same technology is magnified when you first logon to the NxCore servers. Because the client machine has not received the data transmitted before you logged on, the NxCore servers will automatically backfill all the data that was transmitted from midnight to when you first logged on. This process may take a couple minutes depending upon your bandwidth, the exchanges you are receiving, and the time of day. We strongly recommend customers run NxCore Access 24/7/365 to insure you have all of the data and do not need to backfill any data. NxCore Access uses very little of your computer resources, and running it all the time should have little to no impact on your machines performance.

I don't want to leave NxCore Access running all the time. What are my alternatives?

We highly recommend leaving NxCore Access runnin 24/7/365 for reasons stated in previous answer. There is no way to get real time data immediately with out downloading the data from midnight. The morning hours are generally light and you may be able to catch up to real time but there are no guaranties.

I can run NxCore Access all the time, but what if we lose power or our connection is lost. How can we get back up and running quickly?

When your connection is restored to the NxCore servers, NxCore Access is automatically download the data that was transmitted during your outage. You do not need to make a request for the data. If the outage was overnight and extended from one day to the next, NxCore will first download the current day’s data and then the previous day. The previous day's data will be downloaded in the background and shows up as a different color in NxCore Access's bandwidth chart.

What language is the API? What language wrappers are available?

NxCore is native to C, but we do have wrappers for C++, C# and VB. Visit our language wrapper page for information regarding the language wrappers. Please contact if you are interested in downloading the language wrappers.

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How do I ensure that I always use the correct DLLs and header files?

You can use the header files from \Program Files\Nanex\NxCoreAPI, but you MUST copy the NxCoreAPI.dll to another location and always run it from there. This is for two reasons:

  1. to prevent the update from failing because the DLL is in use by your program
  2. to ensure that you have time to test the new DLL with your program.

I received a message about a "install failed" for new NxCoreAPI version, how do I fix it?

You are running the NxCoreAPI.dll from \Program Files\Nanex\NxCoreAPI, and thus it cannot be changed. Read the above FAQ question as to how to change it. It is not imperative that you use the new one immediately -- you could wait until close, and the install will retry.

NxCoreAccess stopped seeing my network drives as archive drives?

If NxCoreAccess is started at boot time or by the NxCoreAccessService, it has a different permission level --- which doesn't have access to network drives.
Just start NxCoreAccess again (while it's running) and it will replace the current running one and (since started by you) will now have elevated privileges.

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I lost some of my old tapes, how do I get them back?

Contact Tech Support via Message in NxCore Access to request the lost tape files. Depending upon how old the tapes and the quantity of deleted files, additional fees may apply. If the tapes are less than 7 days old, NxCore Access will automatically download the files from the NxCore servers. Click on the box with “T” the top left of NxCore Access to view the tapes on your local machine. If NxCore does not download the files you deleted, click on the “Settings” box and check to see if you have Access configured to download hisotrical tapes. In Tape Management you can configure NxCore Access to automatically archive the tape files to a network drive.

I am interested in purchasing historical data, do you have it available to download?

The historical data is provided in the same NxCore tape file format as the real time data. The data is compressed over 90% and synchronized. Your application will process the historical data identical to real time, the only difference is the data will be read from your hard disk instead of from memory.

Yes, we sell historical data, please visit our historical data section for a detailed explanation of what we have to offer.

How do I look for options using APIViewer's filter?

There are two ways to find options using the APIViewer. You can simply put in the root to get all options for that root. For example, filter by oSPY will show only the oSPY root options. To find a specific option the format is oSYMBL_YYDDMSTRIKE. For example, an oSPY April 2010 110 Call is oSPY_1017D110

Category Questions

If I'm looking at a symbol in a tape, occasionally I see 2 NxLastQuote category messages, one with a reasonable price and one with an unreasonable price .. why do I see both?

When looking at Categories, always check the Session Date which the category applies to: pNxCoreMessage->coreHeader.nxSessionDate. For some categories in some contexts, we may send out more than one of the same category for the same symbol. Those are always sent with most recent SessionDate first.

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Network Questions

To help diagnose possible network problems please visit our network troubleshooting page.

NxCore Access keeps telling me to "Standby", how do I get it to work?

Make sure that a firewall is not blocking the traffic for BOTH UDP and TCP. Contact or call 847-501-4787.

What hosts/ports does NxCore use?

Please contact nanex support ( for host and port information.

NxCore Access has a bad connection grade, what can I do to improve it?

The first thing you should check is if your chart looks like any of the pictures on our network troubleshooting page. If that doesn't help make sure that you have followed the suggestions about with your firewall and opening ports. Contact support as well via NxCore's messaging service to try and work out the problem.

I want to have multiple computers running NxCore Access. What can I do?

Contact Jerry Chandler about adding multi-cast licenses. You can have one account act as an NxCore Access Server and multi-cast the data to multiple computers on the same network. All of the computers will receive the exact same data. You may incur additional exchange fees.

I have permission for multi-casting, what do I need to do to set it up?

All the computer must have NxCore Access (the same version must be installed on all the machines) set up and all the computers must be on the same network. All of the computers must have the same DLL version as well. Set up one computer as a multi-cast server in NxCore Settings. The other computer then must be set as multi-cast clients. Contact support via NxCore Access or at if you continue to have problems.

My multi-cast client can't connect to my multi-cast server, how do I fix it?

Check the firewalls on the multi-cast client(s) and server are not blocking the data and are configured to allow data to pass through to the multi-cast client machine.

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Wine Questions

I am running Wine and I not longer am receiving any data! How do I fix it?

The source of why Wine suddenly seizes to receive data is still a bit of a mystery, but we have a solution for the problem. Shut down NxCore Access completely. Once Access is closed, navigate to the registry and delete all the NxCore entries (located at SOFTWARE\Nanex). Then load NxCore Access back up again. It should ask you for your credentials. If that doesn't work shut down NxCore Access and completely uninstall it. Contact with your account number and name to receive the links for a fresh installer. After you receive the links, download NxCore Acces and reinstall the application. Once again, when you load it up it should ask for your credentials. If you continue to have problems, please contact or call 847-501-4787.

If you have a problem that is not covered in the FAQ, please contact or send a message to support via NxCore Access.