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There are multiple reasons that may cause msxml3.dll errors. These include Windows registry issues, malicious software, faulty applications, etc.
Error messages related to the msxml3.dll file can also indicate that the file has been incorrectly installed, corrupted or removed.
If you get the "msxml3.dll is missing" error, you can use one of the following methods to fix the problem.
Method 1: Download Msxml3.dll
Method 2: Fix the missing Msxml3.dll error automatically
Method 3: Update drivers to restore missing .dll files
Method 4: Scan your PC for malware to fix msxml3.dll error
Method 5: Fix Msxml3.dll missing error with System File Checker (SFC)
Method 6: Fix corrupted Msxml3.dll file by performing System Restore
Check out the MSXML Roadmap for any compatibility issues with Windows 2003：