diff --git a/compressed_archive/wrapper.pri b/compressed_archive/wrapper.pri
index 933a27e7..9ae4b25b 100644
--- a/compressed_archive/wrapper.pri
+++ b/compressed_archive/wrapper.pri
@@ -1,6 +1,23 @@
 INCLUDEPATH += $$PWD
 DEPENDPATH += $$PWD
 
+win32 {
+!exists (../compressed_archive/lib7zip) {
+	error(You\'ll need 7zip source code to compile YACReader. \
+	Please check the compressed_archive folder for further instructions.)
+}
+}
+
+unix {
+exists (../compressed_archive/libp7zip) {
+	message(Found p7zip source code...)
+	system(patch -N -p0 -i libp7zip.patch)
+} else {
+	error(You\'ll need 7zip source code to compile YACReader. \
+	Please check the compressed_archive folder for further instructions.)
+}
+}
+
 CONFIG   += precompile_header
 
 win32 {PRECOMPILED_HEADER = $$PWD/StdAfx.h}