Encountering the Excel corruption errors and finding the Excel recovery tools is really a tricky as well as unwanted task. But still excel corruption can't be avoided and may be indicative through some of the error messages. One such error message is as follows:
"Excel found unreadable content in Book_Name. Do you want to recover the contents of this workbook"
This is the error message encountered when you try to open the Excel workbook. Clicking 'Yes' in the dialog box may show you a recovery report:
Removed Records: PivotTable report from /xl/pivotCache/pivotCacheDefinition1.xml part (PivotTable cache)
Opening the same file in the Microsoft SharPoint Web Part report page, the error message may appear like:
"The workbook that you selected cannot be opened. The workbook may be in an unsupported file format, or it may be corrupt. Would you like to try and open this file in Excel?"
The error message is itself stating the cause i.e. corruption. However the other reasons may include problematic nature of the used KPIs (Key Performance Indicators). This is the feature supported by the Excel PivotTable of Analysis Services. KPI is a set of calculations which are defined in an Analysis Services model to represent key business metrics which can be displayed in reports, dashboards, etc. This is possible that one or more KPIs have an expression in the Current Time Member property. So to combat the problem you should try to remove those expressions.
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