Fix Slow Power Query Refresh in Excel on New Windows PCs
Question details
Power Query refresh times have increased drastically on newer Windows machines, taking over an hour compared to a few minutes on older setups.
- Product
- Excel for Microsoft 365
- Device & OS
- Windows 10, Windows 11
- Scenario
- Refreshing data queries using an i5 Navigator 5250 emulator and ODBC connections, as well as executing small file-based queries.
- Observed behavior
- Query refreshes that normally complete in about two minutes now take more than an hour, despite running on modern computers with SSD storage and ample RAM.
Ensure you have administrative privileges on your Windows computer, as you may need to update system ODBC drivers and verify your emulator configuration.
Match ODBC Driver Architecture and Update System Components
Mismatched architectures between Excel and ODBC drivers are a primary cause of severe performance degradation in Power Query.
If you are using 64-bit Excel, you must use a 64-bit ODBC driver to handle memory efficiently. Running a 32-bit driver through a compatibility layer on a 64-bit system can cause extreme slowdowns during data retrieval.
Open Excel, click on 'File', select 'Account', and click 'About Excel'. Note whether your installation is 32-bit or 64-bit.
Press the Windows key, type 'ODBC Data Sources', and open the version (32-bit or 64-bit) that matches your Excel installation. Ensure your specific driver is listed and configured correctly.
Install the latest Windows updates, Microsoft 365 updates (via File > Account > Update Options), and the newest available version of your i5 Navigator emulator.
Isolate Slow Operations and Run Diagnostics
Testing with smaller queries and using Power Query's built-in diagnostics can help identify exactly which step is causing the bottleneck.
Try WPS Office for Fast, Lightweight Data Processing
If complex ODBC integrations, legacy emulator conflicts, and heavy Power Query processes are slowing down your workflow in Microsoft Excel, WPS Office offers a lightning-fast alternative. It is highly optimized for performance and seamlessly compatible with standard spreadsheet formats without draining system resources.
- 1. Download and Install: Get WPS Office from the official website and run the quick installer on your Windows machine.
- 2. Open Your Spreadsheets: Launch WPS Spreadsheets and open your existing .xlsx or .csv files directly without any formatting loss.
- 3. Process Data Quickly: Use built-in fast filtering, pivot tables, and formula functions to process your data smoothly.
Frequently Asked Questions
Why does Power Query slow down on a faster, newer Windows PC?
Performance drops on new hardware often result from mismatched ODBC driver architectures (e.g., using a legacy 32-bit emulator driver with 64-bit Excel) or compatibility issues between newer Windows updates and older data-source software.
How do I know if I am using 32-bit or 64-bit Excel?
Open Excel, click on the 'File' tab, select 'Account', and click the 'About Excel' button. The top line of the resulting dialog box will display your full version number and specify whether it is 32-bit or 64-bit.
Can small file-based queries cause slow refresh times in Power Query?
Yes. If there is an underlying conflict in the data engine, a bug introduced by a recent Office update, or if aggressive antivirus software is scanning temporary files created during the query process, even tiny queries can take abnormally long to refresh.
