Antivirus exclusion for Microsoft Office Web Apps Server 2013

Some time ago I wrote a post about AV exclusions for SharePoint. Today I’m writing to put down some AV exclusions for Office Web Apps, because a client installed AV on their servers and started receiveng errors like:

Error like “ConversionError” and “Conversion failed”.

ULS log path: C:ProgramDataMicrosoftOfficeWebAppsDataLogsULS

For safer side and you can exclude following folder and files. Make your own assumption and set exclusion. There is thumb rule for exclusion list.

Antivirus scanning exclusion:

Folder directory:


C:Program FilesMicrosoft Office Web Apps

Application (.exe):






























More info at:

Hope it helps!

How to use Office Webb Apps in a .Net application

My colleagues were developing a .Net application and they wanted to use the Office Web Apps to previsualise files, such as, word, ppt or pdf.

We were discussing about the issues and finally we opt to implement a server with Office Web Apps and use it to try how to implement it, so let’s go:

We have to take into account that by default the Office Web Apps new farm configuration does not set OpenFromURLEnabled to True. So to use it, it is neccessary to set to True by running the command below in Powershell on the WAC Server

Set-OfficeWebAppsFarm -OpenFromURLEnabled

Setting this propertie to True, Office Web Apps Server provides a page at the address http://OfficeWebAppsServername/op/generate.aspx that you can use to generate links to publicly available documents that have UNC or URLaddresses. When a user selects a generated URL, Online Viewers enable Office Web Apps Server to get the file from its location and then render it by using Office Web Apps.

Next is to create a folder inside the server (or in a NAS or whenever you want), but it is necessary that the computer that run the Office Web Apps farm has permissions on it.


Also it is necessary to share the folder with everyone:


Next step it to generate the URL, so we need to open IE and go to the folowing URL: http:///op/generate.aspx

Use the URL that is next to “InternalURL” when you perform Get-OfficeWebAppsFarm

If you are not using an “InternalURL” then you will obviously have to use “ExternalURL”

Enter the UNC location of the workbook

Click ” Create Link ” and then click “Test this link.”


So, now we have to methods to access to the file:


And an Iframe to insert in a WebApp…


So we can try the previsualization of the file and If this works, then you know the WAC Server can render the workbook and something else is configured incorrectly.

Hope that helps!

Excel Services and Office Web Apps

Be aware that if you would like to use Excel Services for rendering your Excel files instead of using Office Web Apps, you would have to suppress the WOPI Binding that is responsible for viewing of Excel files. This is done through PowerShell in the SharePoint farm, it’s not a WAC setting.

New-SPWOPISuppressionSetting -extension XLSX -Action View

This command will suppress the WOPI Binding for the extension XLSX (Excel files) and for the WOPI ActionView.

It not necessary to iisreset on the SharePoint farm or even the Wopi farm or anything else.

But if you want to check if your files are rendered using WAC or Excel Calc you can take a look to the url showed.

If its viewed using Office Web Apps the URL will look something like this:
but if Excel Calc is rendering the document it should look like the following:

You can also check the WOPI suppression settings using the command Get-SPWOPISuppressionSetting

Finally, If you need to revert your changes, use the command Remove-SPWopiSupressionSetting

Update 2016/05/24: Additionally if any of this works, try to use the commando Remove-SPWopibinding -application “excel” this will remove all the Excel binding in the Wopi farm

Hope it helps!

Maximum Excel Workbook size when using Office Web Apps 2013

Hi all,

Yesterday a client called complaining about when they tries to open a workbook in the browser they got the following error message:


By default, Office Web Apps maximum Excel workbook size = 10 MB


To change the value, you will have to use the following command and define a custom new value for the maximum excel workbook size;


You will have to do an IISRESET on all SP servers to make this change effective

That’s all!

Office Web Apps 2013: How to use custom fonts


If you have custom fonts that you want to be used with Office Web Apps, you need to be aware of the following:

  • Fonts must be .oft files, .tiff files does not work with Office Web Apps Server 2013
  • .oft files have to be installed locally in every Office Web Apps Server in the farm, as well as in user’s local machines
  • Every time a new Font is installed, is it necessary to restart every Office Web Apps Server
  • Fonts must be installed as administrator
  • Fonts will not appear in the dropdown list of fonts, but the Font is it possible to be searched using the searchbox. Note: It has to be spelled exactly as the name of the Font.

That’s all, hope it helps!

Office Web Apps: Lesson Learned

This entry will explain my own experience after developing a Project with Office Web Apps and SharePoint 2013.

Due of the customer requierements we needed to deactivate the OneNote documents previews on search centers, document libraries, etc.. This was not a problema, because it was pretty simple to do it with one powershell command (if you are in the same situation and you didn´t know how to do it, let me know and I’ll try to help you).

But some time ago after deactivating the preview, we were receiving complaints from the users, because they were receiveng errorrs when they tried to créate OneNote documents from library.

We were checking this behaviour and we realized that the preview was throwing this error, so to solve this we needed to hide by CSS the button to créate OneNote documents, by this way the user will not have the OneNote option and he/she will not be able to reproduce the error again.

So, keep in mind when you are working with Office Web Apps it is not recommended to deactivate some document previews, it’s not possible to be sure that the preview has been deactivated completely and it will cause some problems in a near future.

Office Web Apps 2013: Delete extension

This post will explain how to remove an Office Web Apps extension to not to do previews in Shareoint 2013.

In this case, we will remove an entire “OneNote” application, but of course it ca be done at doctype level.

First of all, is it necessary to open as administrator an Sharepoint 2013 Shell and type the following:

remove-spwopibinding -application “Onenote”

In case we want to re-add the application removed, we have to type the following:

new-spwopibinding -application “onenote” -servername “OWAServerName”

Hope it helps!