SharePoint 2013: Excel web access web part errors

If you have recently migrated from SharePoint 2010 to SharePoint 2013 or if you are configuring excel web access web part for SharePoint 2013 with named component, you might notice that you Excel web access web parts are showing some error or not showing any data even after you add your excel file location to Trusted locations in excel service application.

There are multiple reasons behind this behavior of excel web access web part.

1. If you are getting error "Workbook cannot be opened" as shown in below image, It is related to permissions to the service account used for Excel services. As all your excel files are stored in Content DB, service account used for Excel service should be having access to all respective web applications.

You can use following cmdlets to get this issue resolved:

$webApplication = Get-SPWebApplication –Identity <URL of the Web application>

$webApplication.GrantAccessToProcessIdentity("<insert service account>")

You have to perform this action for all your web applications using excel web access web parts

2. You see the error "We're sorry, we couldn't open your workbook. It is possibly corrupt or using a file format that's not supported. Do you want to try and open this file in excel?" as shown in below image.

This error is very miss leading at times. There are chances that your excel file is corrupt but you better be sure about this.

To verify

1. Download the file to local system and open it in excel. If it does not open correctly then you can say it is  corrupt and need to be changed.
2.  If it opens correctly then nothing is wrong with file, you have to check for other resolution. In this case it might be the fact that you have not started Excel web service on all your web front end servers. 

Once you start the excel web service on all your web front end servers. This issue will be gone.

3. After getting rid off above issues, you notice nothing is coming up in excel web part not even error. It is showing sort of blank. This could happen to the web part if you are running RTM build for SharePoint 2013. If you have configured the excel web access web part with "Named component" you will get this error in SharePoint 2013 RTM. This is a known issue and is resolved in March 2013 PU for SharePoint 2013.

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