Call Us: 800-321-6786 - Mail:

groov Troubleshooting Q&A

Troubleshooting Q&A

Basic Communications
Using groov
Viewing interfaces
Contacting Product Support

All logos and product names used herein are trademarks or registered trademarks of their respective companies or organizations.

Basic Communications

A: Make sure you have Administrator privileges on the PC where you’re installing groov Server. If you do and you’re still having trouble, contact Product Support.
A: Make sure you’ve typed the URL correctly, including the s:

  • If you’re trying to reach groov from the same computer groov Server is running on, type https://localhost as the URL.
  • If you’re on a different computer or a mobile device, type https:// plus the hostname or IP address of the computer groov Server is running on. Example: https://jsmith-w10

Make sure groov Server is running. Go to the computer where it’s installed and look for the groov Monitor icon in the system tray (bottom right corner of the screen). A green triangle indicates it’s running. If you see a red square, right-click the icon and choose Start groov Server from the popup menu.

If you still can’t reach groov, there might be a conflict with another service running on the groov Server computer. In this case, you may need to change the port groov Server uses to run. First consult with your IT manager, and then follow steps in the groov User’s Guide, Chapter 7 (Troubleshooting).

For more information on networking, see the Guide to Networking groov.

A: First, make sure you’ve typed the URL accurately and included the “s“: https:// plus the groov Box hostname or IP address. Examples:

  • https://Opto-06-51-f2

Make sure your computer network is plugged into ETH0 on the groov Box. Don’t use ETH1 right now.

If you still can’t reach the Box, your network is set up differently. That’s OK. If you like videos, watch groov Find and get going again. Or, determine the following information about your network and your computer:

  • Does your network have a DHCP server?
  • Does your network have a DNS server?
  • Does your computer have more than one network interface card (NIC)?

Then see the next questions on these subjects for more answers.

A: A DHCP server automatically assigns IP addresses to devices on the network, which is what the groov Box expects. If you have no DHCP, work with your IT Department to choose a static IPv4 address for the groov Box. To assign the fixed IP address, you’ll need:

  • a Windows PC on the same network subnet as the groov Box
  • groov Find utility (on the CD that came with the groov Box)
  • groov Box User’s Guide Chapter 4–Follow steps to assign the static IP address to the Box.

Once you’ve assigned the static IP address, open your web browser and for the URL enter https:// plus the IP address you assigned to groov. For example:

For more help on networking, see the Guide to Networking groov.

A: A DNS (domain name server) keeps track of the unique hostname for each device on the network, so you can find it by name even if its IP address changes. If your network has no DNS, you won’t be able to access the groov Box using its hostname, but you can access it using its IP address.

To determine the IP address, you’ll need:

  • a Windows PC on the same network subnet as the groov Box
  • groov Find utility (on the CD that came with the groov Box)
  • groov Box User’s Guide Chapter 2–See steps to start groov using groov Find.

Once you’ve found your groov Box in groov Find, click the link to set up the Box. Also make a note of the IP address shown, so later you can use it in your web browser instead of the hostname: for the URL enter https:// plus the Box’s IP address. For example:

For more help with networking, see the Guide to Networking groov.

A: More than one NIC can cause a problem when you’re trying to communicate with a groov Box using your browser and the groov Box’s hostname.

Each NIC communicates on a separate network subnet. You may have one network subnet set up for your computers and a second one set up for your control system, for example (this is a pretty common scenario, and in fact we recommend it for security).

Make sure you’re trying to reach the groov Box using the NIC for the network subnet it is on. You could unplug the Ethernet cable from your controller network NIC to force the PC to look for the groov Box on the computer network. Then try again using your browser and the groov Box’s hostname.

If your control system and your computers are on separate network subnets, you’ll need to set up ETH1 on the groov Box in order to reach your control system. See the groov Box User’s Guide (Chapter 4) for instructions. For lots more on networking, see the Guide to Networking groov

A:  Most likely you didn’t wait quite long enough after turning the Box on. It’s important to wait until the groov Box’s SYS LED has stopped blinking. If you try to connect to it before then, the DNS may not have had enough time to register the hostname.

If this happens, you can:

  • On any computer, connect to the groov Box using its IP address instead of its hostname.
  • On a Windows computer, open up a command prompt and type: ipconfig /flushdns. After that you should be able to connect to the groov Box using its hostname.
A: The settings on your phone can cause a connection to the soft access point on the groov Box to disconnect.

If you are a Sprint customer: Try turning off the Connections Optimizer. On your phone, go to Settings > More… > Mobile Networks > Connections Optimizer and uncheck the box for this feature.

If you are not a Sprint customer: On your phone, go to Settings > Wifi > Advanced and make sure that the “Avoid poor Internet connection” and “Internet Unavailable” options are unchecked.

A: Modbus/TCP devices, though based on a standard protocol, may be set up differently from one another. Some use zero-based addressing and some use one-based addressing. Some devices don’t support all Modbus functions. Modbus/TCP devices also vary in the way they present float data. And device documentation sometimes doesn’t specify how the device is set up.

If you’re having trouble reading or writing to your device, or if the data is clearly wrong, start by reading the sections “Modbus Protocol Settings” and “Data Interpretation Settings” in the groov Build and View User’s Guide. Consult your device’s documentation for help, and change the settings for your Modbus device in Configure > Devices and Tags. You may need to try different combinations of settings to see what works.

If data from the Modbus device doesn’t make any sense (looks like garbage or is completely abnormal), change the “Use base one addressing” setting. Or change the combination of Data Interpretation Settings.

Probably the best way to figure out how to connect with any Modbus/TCP device and get the data presented in the right format is to use a Modbus/TCP test utility, like ModScan32 from Our Product Support Group recommends this utility.

You can also use the utility Wireshark ( to see the Modbus/TCP traffic between your devices, so you know exactly what message was sent and what the specific reply was.

If you need help, be sure to contact Opto 22 Product Support. Product support is free.

Using groov

A: If the groov Box or groov Server PC and your computer are on the same network, you can do one of two things:

  1. Accept the security warning and continue. The data flowing between your browser and groov is still encrypted and very secure.
  2. Use a self-signed certificate. When you use a self-signed certificate, you won’t be slowed down by the warning; you’ll go straight to groov.
  • For the groov Box: Use the self-signed certificate included with your groov Box. See the groov Box User’s Guide (Chapter 4) for instructions.
  • For groov Server: See the groov Server User’s Guide (Chapter 2) for steps to create a self-signed certificate.

If you’re accessing groov from outside the network the groov Box or groov Server PC is on (for example, over the Internet), Opto 22 strongly recommends you purchase a Security Certificate from a Certificate Authority (see the next question). A Certificate Authority is a third party that verifies to your web browser that the site you’re going to (in this case, the groov Box or groov Server PC) is genuine. Once you have the Certificate, you’ll no longer see the warning.

For more information on networking groov, see the Guide to Networking groov.

A: A number of companies offer Security Certificates; just search and choose the one you want.

As part of the purchase, you’ll need to generate a Certificate Signing Request (CSR) file to send to the Certificate Authority. A CSR is a block of encrypted text that contains information needed for the certificate.

If you do purchase a third-party certificate, keep in mind that a certificate can be used with any operating system but that groov requires the certificate to be a PEM file. If you are asked to select an operating system, you can safely select “other” if that is an option, but it’s OK to choose any type of operating system since the certificate is not OS dependent. The important thing is to select PEM as the format, and then cut and paste the certificate into the place provided in groov. See the groov Box User’s Guide or groov Server User’s Guide for instructions.

A: If your browser’s font sizes are too big, buttons like “Create User” and “Edit Group” may be cut off. In your browser, change the font size to be smaller. For example, in Firefox, choose Options from the Tools menu, click Content, and reduce the size of the font.
A: In groov Build, choose Configure > Accounts. If the software user already exists, find its name in the list and read across to the API Key column.

If the software user doesn’t exist yet, click Create New User. Enter a username, choose a Role of Editor or Admin, and enter a password (which won’t be used). After you click Create User, you’ll see the username and API key in the list.

If you need to generate a new API key, choose Configure > Accounts, find the software username in the list, and click the pencil icon to edit the user. Click the Generate button. Once you click Update User, the new API key will be shown in the list. The old key is automatically disabled.

A: Probably a setting or two that needs to be changed. Take a look at our short KEPServerEX Settings for groov Technical Note for answers.
A: Check the settings in Ignition as described in the short Ignition OPC-UA Server Settings for groov Technical Note. That should solve the problem.
A: When you buy groov you receive one free year of maintenance, which means you can download and install all the updates released during that time. When the year is just about up, we’ll remind you to renew. Follow the link in the reminder, or go to For more information on groov Maintenance and how to renew, see the groov Maintenance Technical Note.
A: Are your Opto 22 control system and your computers on separate network subnets? We recommend this setup for security reasons, and the groov Box is designed to work this way. Here’s what to do so groov can find your PAC.

With a groov Box:

  1. Plug the control network into ETH1 on the groov Box. (Remember, your computer network is plugged into ETH0. The two Ethernet network interfaces on the Box are independent, so that keeps the two network subnets separate.)
  2. Follow steps in the groov Box User’s Guide (Chapter 4) to configure the ETH1 connection using groov Admin.
  3. Now try configuring your controller again. This time groov should be able to find it.

For more information on networking, see the Guide to Networking groov.

A: (Opto 22 systems only) Your SNAP PAC controller is running the control program (strategy) you built in PAC Control. When you saved that strategy, the .idb.txt file was automatically created on your PC in the same directory as your other strategy files. If you’re now using a different PC, you’ll need to get the .idb.txt file from the other computer.

If your computer hides common file type extensions (some do), you’ll see two files with the same name, the name of your strategy. Just select the file that does not have the PAC Control icon next to it.

NOTE: If you’re using groov with an OptoEMU Sensor, you can get the OptoEMU Sensor.idb.txt file on

Viewing Interfaces

A: Two possibilities:

  1. Your current web browser may not fully support the standards groov is based on. Try downloading the latest version of your browser. Or try a different browser. We often recommend Firefox or Chrome, but your device might work better with Safari or Internet Explorer 10 or higher.
  2. You may be logged in as a user who doesn’t have access to any pages. Go to groov Build and check your users and groups to make sure the user has access. See the groov User’s Guide (Chapter 3) for help.
A: First, make sure you have at least the minimum OS for your device:

  • Android: 4.0.1 (Ice Cream Sandwich)
  • iOS: 9.0

If you’re still having problems, don’t worry. We’ve seen some quirks depending on your device and browser. Here are some things to try.

  • Try adding your own company domain to the hostname of the groov Box. Sometimes the DNS (domain name server) won’t resolve the hostname unless you add your domain. Example: instead of https://opto-02-81-c2 try (Put in your domain instead of Note the period between the hostname and domain.)
  • Try adding the port number to the hostname. Port 443 is the default; port 8443 is the secondary, so try them in that order. For example: instead of https://opto-02-81-c2 try https://opto-02-81-c2:443 (Note the colon between the hostname and port.)
A: If a gadget is grayed out with a yellow triangle, one of these communication problems is occurring:

  • groov View is not communicating with the groov Box or Server.
  • groov is not communicating with the Modbus/TCP device, PAC controller, or OPC UA server
  • the Modbus device, PAC controller, or OPC UA server is not communicating with your control system or equipment

Click the yellow triangle on the gadget to help discover the problem. Once you’ve fixed communications, groov View will automatically restore the gadget to working order.

NOTE: groov polls the Modbus/TCP device, PAC controller, or OPC UA server for data once per second. This frequency cannot currently be changed.

A: If a gadget is grayed out with a no-tag symbol, the gadget is not associated with a tag from your tag database. Go into groov Build and tag the gadget. Once you’ve done that, groov View will automatically restore the gadget to working order.
A: You may have lost connection with your Modbus/TCP device, PAC controller, or OPC UA server. If so, groov can’t check the tags it’s supposed to be watching, so you won’t receive event notifications for those tags.

Click the Events (bell) icon to open the Events Viewer. If you see the “Could not connect…” error, you’ll need to track down what happened to your lost connection. For more help, see Viewing Events in the groov User’s Guide.

Contacting Product Support

If these answers don’t help, please contact Opto 22 Product Support for groov. The experienced engineers in our Temecula, California, headquarters are available to help you Monday through Friday from 7 a.m. to  5 p.m. Pacific Time.

Product support is FREE.
Phone: 951-695-3080
Toll-free (in the U.S. and Canada): 800-835-6786

Other Resources for Help

Two other resources for help are available 24 hours a day, 7 days a week:

  • groov OptoForum—Post your question on the groov forum and get answers from groov-savvy people all over the world.
  • OptoKnowledge Base—If your issue isn’t covered in this Q&A, you can check KB articles for fixes and workarounds.
Back to Top