How to fix data mismatch issues in Excel

When connecting Excel to Windsor.ai, you might occasionally see data mismatches — incorrect numbers, missing fields, formatting issues, or outdated values.

This guide explains the most common types and causes of Excel discrepancies, as well as how to resolve them, ensuring that your Excel reports remain accurate and reliable.

• Date range, filter, or aggregation mismatches
• Invalid API URL
• Data not refreshing correctly
• Decimal separator issues (especially in EU regions)
• Data formatting or type inconsistencies
• Schema changes in source data
• API or query limitations
• Manual edits in Excel are disrupting the structure

Incorrect totals or missing rows often happen when filters, selected fields, or date ranges aren’t aligned with what you require in the Excel workbook.

Troubleshooting steps:

• Ensure the data in the Windsor.ai preview dashboard aligns with your expectations, as it will be transferred to Excel in this way.
• Confirm that the correct date range, metrics, and fields are selected.

• Ensure filters match what you expect (e.g., campaign name, channel, country).
• Make sure the required data sources are selected in the Windsor.ai data preview dashboard.

• Compare the results between Excel and Windsor’s data preview.

If your API URL is invalid or has expired, go to the Windsor.ai data preview dashboard, select “Excel” as your data destination, and copy your valid API URL from the instructions.

Then paste the correct API URL in your Excel workbook.

If your data appears outdated or incomplete, your workbook may not be retrieving the latest information from Windsor.

Troubleshooting steps:

• Refresh data in Excel. Go to Data -> Queries & Connections -> Right Click on your Query -> Refresh.

• Windsor.ai caches data for 6 hours, but you can clear that cache manually anytime for real-time data updates.

In many European regions, Excel uses a comma (,) as the decimal separator instead of a dot (.). This can lead to 10.0 being misinterpreted as 100, distorting metrics such as spend or sessions.

Troubleshooting steps:

• In Excel, go to File -> Options -> Advanced -> Use system separators
• Uncheck the box in the ‘Use system separators’ field and manually set:
  • Decimal separator: .
  • Thousands separator: ,

Windsor sends clean, structured data, but Excel may misinterpret fields (e.g., numbers as text, dates as plain strings, etc.).

Troubleshooting steps:

• Select the tab Home -> Format Cells  -> Set the correct format (Number, Date, etc.).
• Use VALUE() or DATEVALUE() functions if necessary to convert data.
• Look for green triangles in the top-left of cells (Excel warnings about formats).

If the data source (e.g., Google Ads, GA4, Facebook Ads) changes — removing, renaming, or reordering fields — it may break or misalign the data imported into Excel.

Troubleshooting steps:

• Revisit your query in Windsor.ai, select updated fields, and refresh the data in Excel.
• In Excel, delete or re-map outdated columns.
• Match data in the Windsor.ai data preview dashboard and Excel workbook.

Enormous datasets or complex queries may exceed API limits or Excel’s data handling capacity, resulting in cutoff data or errors.

Troubleshooting steps:

• An Excel spreadsheet can handle only a certain number of rows and cells. If you’re working with large datasets, simplify your query by selecting fewer fields or narrowing the date range. Here are the limitations of Excel that you should consider:

Rows per sheet: 1,048,576 – applies to Excel 365, 2016+, 2013, 2010.

Columns per sheet: 16,384 (up to column XFD) – same across most modern versions.

File size (Excel Desktop): ~2 GB max – performance may degrade around 100 MB.

File size (Excel for Web): ~50 MB – large files may fail to open or load slowly.

• Check Windsor.ai API/data sources/refresh quotas: If you’ve reached your API/data sources/refresh usage limits or are being rate-limited, your data may fail to load completely or update reliably. You can resolve these issues by choosing the correct Windsor.ai plan for your needs.

• Check API limits for each data source: Many sources impose their own rate limits and data availability rules. Refer to their official API documentation to understand how these may affect data freshness, completeness, and performance.
• Keep queries simple: Avoid stacking too many filters, joins, or complex calculated fields in one request, as this can slow down the response or cause the data to load partially.
• Ensure complete data retrieval: If your data spans multiple API pages, ensure that pagination settings are properly utilized to collect all available records from Windsor.ai.

Manually editing cells within the imported data table can corrupt refresh logic or prevent Excel from updating properly.

Troubleshooting steps:

• Use a dedicated sheet for Windsor.ai data: Keep imported data separate from your working sheets to prevent accidental edits and ensure clean refreshes.
• Perform calculations and formatting in a separate tab: Reference the raw data in a new sheet for analysis and visualization. This protects your work from being overwritten during updates.
• Avoid editing headers or inserting rows/columns: Changing the structure of the imported table can break refreshes and data references. Keep the format as-is for stability.

By following these troubleshooting steps, users can resolve common data mismatches when streaming data to Excel via Windsor.ai.

If the issue persists, contact our customer support for further assistance.

Please, follow this quick guide to effectively report on your data discrepancy: https://windsor.ai/documentation/how-to-report-data-integrity-mismatch-issues. In this format, our dev team will be able to identify the problem much quicker.

Usually, investigating data discrepancies takes time (1-3 days), so it’s better to organize the report and send it to [email protected]. We’ll take a detailed look and reply to you as soon as we find a resolution.