diff --git a/build.sh b/build.sh
index 922eaca7a589d50ea4370d98856da691b9ee5b13..56dc7a93991d08324b88b3bc5d0d9731a488afb1 100755
--- a/build.sh
+++ b/build.sh
@@ -383,6 +383,7 @@ build_generic_win32()
 	cp $ROOT/3rdparty/boinc/lib/boinc_win.h $ROOT/install/include/BOINC >> $LOGFILE 2>&1 || failure
 	cp $ROOT/3rdparty/boinc/lib/common_defs.h $ROOT/install/include/BOINC >> $LOGFILE 2>&1 || failure
 	cp $ROOT/3rdparty/boinc/lib/diagnostics.h $ROOT/install/include/BOINC >> $LOGFILE 2>&1 || failure
+	cp $ROOT/3rdparty/boinc/lib/filesys.h $ROOT/install/include/BOINC >> $LOGFILE 2>&1 || failure
 	cp $ROOT/3rdparty/boinc/lib/hostinfo.h $ROOT/install/include/BOINC >> $LOGFILE 2>&1 || failure
 	cp $ROOT/3rdparty/boinc/lib/proxy_info.h $ROOT/install/include/BOINC >> $LOGFILE 2>&1 || failure
 	cp $ROOT/3rdparty/boinc/lib/prefs.h $ROOT/install/include/BOINC >> $LOGFILE 2>&1 || failure