diff --git a/compressed_archive/compressed_archive.cpp b/compressed_archive/compressed_archive.cpp
index e4f1efac..ab80511a 100644
--- a/compressed_archive/compressed_archive.cpp
+++ b/compressed_archive/compressed_archive.cpp
@@ -44,10 +44,12 @@ std::vector<GUID> supportedFileFormats (_supportedFileFormats, _supportedFileFor
 DEFINE_GUID(IID_InArchive,                0x23170F69, 0x40C1, 0x278A, 0x00, 0x00, 0x00, 0x06, 0x00, 0x60, 0x00, 0x00);
 DEFINE_GUID(IID_ISetCompressCodecsInfo,   0x23170F69, 0x40C1, 0x278A, 0x00, 0x00, 0x00, 0x04, 0x00, 0x61, 0x00, 0x00);
 
+#ifdef Q_OS_UNIX
 DEFINE_GUID(IID_IOutStream,   0x23170F69, 0x40C1, 0x278A, 0x00, 0x00, 0x00, 0x03, 0x00, 0x04, 0x00, 0x00);
 DEFINE_GUID(IID_IInStream,   0x23170F69, 0x40C1, 0x278A, 0x00, 0x00, 0x00, 0x03, 0x00, 0x03, 0x00, 0x00);
 DEFINE_GUID(IID_IStreamGetSize,   0x23170F69, 0x40C1, 0x278A, 0x00, 0x00, 0x00, 0x03, 0x00, 0x06, 0x00, 0x00);
 DEFINE_GUID(IID_ISequentialInStream,   0x23170F69, 0x40C1, 0x278A, 0x00, 0x00, 0x00, 0x03, 0x00, 0x01, 0x00, 0x00);
+#endif
 
 struct SevenZipInterface {
 	CreateObjectFunc createObjectFunc;