Version 5 of OAK Now Available

The fifth-generation of the Operis Analysis Kit software is now available. Find out what's new

What's New

Your answers to frequently asked questions

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OAK Version

Which is the latest version of OAK?

OAK 5.00.000

I've got an earlier version of OAK. How is the latest version different?

The latest version of OAK (version 5) was launched on the 1st of July 2020 and represents a major change to the previous version – OAK 4.

OAK 5 is now a subscription based software with a completely refreshed user interface, significant performance improvements and a new feature – the Formula Walker – which allows users to easily navigate across formulae precedents and dependents as well as creating bookmarks with comments on any of the investigated cells.

OAK 4 license holders can benefit of a 50% discount on the annual plan for the first year – this campaign will be available for all OAK 4 license holders that purchased their OAK 4 license from the 1st March 2020 and will be available until 31st July 2020. All other OAK 4 license holders that wish to upgrade will have a 25% discount on the 1st annual subscriptions (campaign running until 01/10/2020) .

Nevertheless, we still support our OAK 4 users by fixing reported bugs but no further development will be carried out on OAK 4.

A version history that sets out the differences between revisions to OAK 4 and OAK 5 is set out in the online help document.

I've got an earlier version of OAK. What do I have to do to get the latest version?

If you have version 5 of OAK, it will alert you to the appearance of a new update and ask for your authorisation to download and install it without any upgrade costs as your subscription includes all updates and versions.

If you have version 4 or earlier of OAK, it will alert you to the appearance of a new update and ask for your authorisation to download and install it. But you will need to subscribe an OAK 5 plan if you want our latest version.

The automatic updating feature built into OAK may be prevented from working by your firewall security software. In such circumstances you should download the latest OAK5.msi file and double click on it to install the upgrade. You may need help from your IT department to do this.

Will OAK work on the Apple Mac?

OAK 5 is a Windows-only application, and will not work on the Apple Mac, unless you run it in Windows using virtualization software such as VMWare Fusion or Parallels Desktop, with the Windows version of Excel. We do not officially support this.

Does OAK work in 32-bit and 64-bit Excel?

Yes. The single OAK5 msi file installs OAK and registers it for use in both 32-bit and 64-bit Excel.


My computer won't let me download OAK. What can I do?

Some companies set up firewalls to prevent employees from downloading executable files. Companies that do that will probably also prevent executable files from being sent by email, and prevent executable files that do arrive from being installed on workstations except by designated staff. Your best option is therefore to get help from your IT department.

If you wish to try yourself, you can:

  • Download in a location not controlled by the firewall and transfer it to your computer using a memory stick
  • Ask oak@operis.com to email the file

Will OAK install in Windows 8 or Windows 10?


I downloaded OAK to my Apple Mac to use in Parallels Desktop, but the installer says the version of the file is not compatible with the version of Windows I'm running.

While we don’t officially support the running of OAK in Windows in the Parallels Desktop environment, we suggest you try downloading the installer using Internet Explorer rather than Safari.

Does OAK work on my Microsoft Office - Windows Store Edition?

Not yet. OAK only runs in the click-to-run edition of O365, not the Windows Store edition.
Check which version you have on the Office Support website


I have a computer at work and a computer at home. Can I use OAK on both of them?

If you are using OAK 5 you can login on your OAK on any device once you have installed it. But it will not be possible to have concurrent sessions with the same login name unless your OAK subscription plan has available seats (the quantity of users that you have purchased with your plan).

If you are using OAK 4 please contact Operis explaining that at any moment you could be using one computer or the other, but never both, we will enable a second activation of your serial number for the second machine.

I have switched to using a new computer. What do I have to do to get OAK to work on the new machine?

If you are using OAK 5, you just need to install OAK on the new computer (installers are available on your Operis Customer Portal) and log in with your email address and password. For other scenarios, see the item “An employee in my company no longer needs OAK. How can I transfer it to another?”

If you are using any version between OAK 4.3 and 4.4 on the old and new computer, transfer a serial number from the old computer. Then activate your serial number on the new computer.

An employee in my company no longer needs OAK. How can I transfer it to another machine?

Your OAK 5 subscription allows you to manage the users of your OAK license by accessing the Operis Customer Portal / Manage OAK Subscriptions. Here you can add, update or remove users from your OAK subscription plan at anytime and without the need to contact Operis. Just download OAK from the portal and log in with the user’s email address.

If you are using OAK 4.3 or 4.4 on the old and new computers, you would perform a serial number transfer on the old computer. Download OAK and install it on the new computer. Then activate your serial number on the new computer. If you cannot perform the serial number transfer on the old computer, send your serial number to Operis, explaining that you wish to transfer OAK to the new computer. We can deactivate your serial number for re-use on the new computer.

If you have been using OAK 4.0 to 4.2, and you have OAK 4.3 or 4.4 on the new computer, perform a serial number exchange, then proceed as for OAK 4.3 or 4.4.

If you are moving from OAK 4.0 to 4.2 on the old and new computer, please email your new product ID to Operis explaining that you wish to transfer OAK to a new computer, and also read about serial number transfers so that you can see how upgrading to OAK 4.3 or later helps you do these transfers without the delays associated with support requests.

Will my OAK version 5 work if I do not have access to the Internet?

Being a subscription-based license, OAK 5 will need to regularly check your subscription status to confirm that it is active and that there are no concurrent active sessions on the same email address. If OAK 5 fails to check the subscription server, it will start a grace period of 3 days where you can still use OAK – especially useful when travelling.

If after the grace period no connection has been made, OAK 5 will stop working until a connection to our subscription server is re-established.

Enabling/disabling OAK

How can I turn OAK off?

You can instruct Excel whether or not to load OAK through the Add-Ins Manager.

OAK has disappeared from the ribbon or menu and the COM Add-ins manager doesn't activate it. How can I get it back?

Excel has probably placed OAK in the Disabled Items list. To make it available again, the process is different in Excel 2007-2016.

First you need to go to the Disabled Items manager:

For Excel 2007, click the Office Button, then Excel Options.

For Excel 2010-2016, click the File button then the Options button.

Then for Excel 2007 to 2016, go to the Add-ins tab. Locate the “Manage” drop down box and set its value to “Disabled Items”. Click the “Go” button.

Highlight OAK in the list, then click “Enable”.

Close the Disabled Items window. You may need to re-enable OAK in the COM Add-ins manager.

Hint: This is something OAK users are fairly likely to encounter, with OAK and other add-ins. If you want to practice the process, try the following:

Activate one of OAK’s dialogs, e.g. compare workbooks, but don’t click the Compare button on the options window, just leave it there waiting for input. Then use Task Manager to end the Excel process. Then, start Excel again. You may be prompted to disable the Operis Analysis Kit – click yes. In any case, you’re likely to find that OAK has been sent to the disabled items list, whereby you can perform the above procedure to release it.

OAK has disappeared from the ribbon, menu and disabled items, and only re-installation restores it temporarily. What can I do?

While it hasn’t been confirmed, we have observed cases where it seems that OAK’s COM registrations get deleted by unknown processes on the computers of users in some IT environments. In this case, you need to ensure the IT staff make sure that their systems are configured to permit the COM registrations that OAK’s installer requires.

Managing my OAK subscriptions

Which email address should I use to log in on my OAK add-in?

If you bought a single OAK subscription you must use the same email address as the one on the checkout page during the purchase – either the billing email address or the one that was entered on the field “End-user email address” also on the checkout page.

If you acquired multiple OAK subscriptions (by setting a quantity > 1 on the checkout page) then either the billing email address or any of the email addresses defined on the “End-user email address” field will provide access to the OAK add-in.

When trying to log in, I keep getting the message “Unable to contact the OAK subscription server.”

As previously mentioned , OAK needs to reach the OAK subscription server to validate your subscription. If there is some sort of firewall on your IT infrastructure, that access will be denied.

Please make sure that your computer can reach the following address:  4uc72qq7.operis.com:4005

Can I change my login email address or any of the users under my OAK subscription?

Upon the payment being successful on the checkout page, you will receive an order confirmation email where a link to your Operis Customer Portal will be provided. You will also receive from Operis a confirmation email with your Portal user name (email address by default) and the request to set up a password.

Once you complete the portal registration a “Manage OAK Subscriptions” on the main portal page you will be able to you add, update and remove users email addresses associated with your OAK subscription.

Can I cancel my OAK subscription at any time?


Your Operis Customer Portal also offers access to your subscription status and details where you can update your payment details or cancel your OAK subscription. Because both monthly and annual plans are prepaid, once you cancel your OAK subscription you will still have access through the paid period.

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