Special European characters in SDE data become invalid if a .Net application uses .NET Framework's Performance Counter, System.Diagnostics.PerformanceCounter.
.Net Performance Counter sets C run time locale to OEM code page, however ArcObjects expects data coming from SDE to be in ANSI code page and converts data to Unicode code page for internal processing.
If data coming from SDE is converted to OEM code page by the Performance Counter, the subsequent ANSI to Unicode code page conversion creates invalid data.
See the link in the Relation Information section for more information on what a code page is.
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