diff --git a/dist/OBS_debian/debian.control b/dist/OBS_debian/debian.control
index 73c101e4a..5e7ea1302 100644
--- a/dist/OBS_debian/debian.control
+++ b/dist/OBS_debian/debian.control
@@ -16,6 +16,7 @@ Vcs-Browser: https://bitbucket.org/dismine/valentina
 Package: valentina
 Architecture: i386 amd64
 Depends: libc6 (>= 2.4), libgcc1 (>= 1:4.1.1), libqt5core5a (>= 5.2.0) | libqt5core5 (>= 5.2.0), libqt5gui5 (>= 5.2.0) | libqt5gui5-gles (>= 5.2.0), libqt5printsupport5 (>= 5.2.0), libqt5svg5 (>= 5.2.0), libqt5widgets5 (>= 5.2.0), libqt5xml5 (>= 5.2.0), libqt5xmlpatterns5 (>= 5.2.0), libstdc++6 (>= 4.6), xpdf
+Conflicts: seamly2d
 Description: Pattern making program.
  Valentina is a cross-platform patternmaking program which allows designers 
  to create and model patterns of clothing. This software allows pattern 
diff --git a/dist/debian/control b/dist/debian/control
index 73c101e4a..5e7ea1302 100644
--- a/dist/debian/control
+++ b/dist/debian/control
@@ -16,6 +16,7 @@ Vcs-Browser: https://bitbucket.org/dismine/valentina
 Package: valentina
 Architecture: i386 amd64
 Depends: libc6 (>= 2.4), libgcc1 (>= 1:4.1.1), libqt5core5a (>= 5.2.0) | libqt5core5 (>= 5.2.0), libqt5gui5 (>= 5.2.0) | libqt5gui5-gles (>= 5.2.0), libqt5printsupport5 (>= 5.2.0), libqt5svg5 (>= 5.2.0), libqt5widgets5 (>= 5.2.0), libqt5xml5 (>= 5.2.0), libqt5xmlpatterns5 (>= 5.2.0), libstdc++6 (>= 4.6), xpdf
+Conflicts: seamly2d
 Description: Pattern making program.
  Valentina is a cross-platform patternmaking program which allows designers 
  to create and model patterns of clothing. This software allows pattern 
diff --git a/dist/rpm/valentina.spec b/dist/rpm/valentina.spec
index 7725a4196..7e6d781e0 100644
--- a/dist/rpm/valentina.spec
+++ b/dist/rpm/valentina.spec
@@ -6,6 +6,8 @@ Requires(postun): /sbin/ldconfig
 Requires(post): desktop-file-utils
 Requires(postun): desktop-file-utils
 
+Conflicts: seamly2d
+
 %if 0%{?fedora_version} > 0 || 0%{?rhel_version} >= 700 || 0%{?centos_version} >= 700
 BuildRequires: qt5-qtbase-devel >= 5.2.0
 BuildRequires: pkgconfig(Qt5Svg)
diff --git a/dist/win/inno/valentina.iss b/dist/win/inno/valentina.iss
index d2424c6f0..bba79aff4 100644
--- a/dist/win/inno/valentina.iss
+++ b/dist/win/inno/valentina.iss
@@ -6,11 +6,12 @@
 #define MyAppPublisher "Roman Telezhynskyi"
 #define MyAppURL "http://www.valentina-project.org/"
 #define MyAppExeName "valentina.exe"
-#define MyAppCopyright "(C) 2013-2017 Valentina project"
+#define MyAppCopyright "(C) 2013-2018 Valentina project"
 #define MyDateTimeString GetDateTimeString('yyyymmddhhnnss', '', '');
 ; Appstatus: "" = release, "b" = beta, "a" = alpha
 ; this only modifies the resulting exe name of the installer package ;-)
 #define MyAppStatus "a"
+#define ConflictingAppId "{7081AEC7-38FC-479F-B712-DB073BB76513}"
 
 [Setup]
 ; NOTE: The value of AppId uniquely identifies this application.
@@ -416,29 +417,37 @@ var
  InstallationCanceledMessage : String;
 
  begin
-  // Create a mutex for the installer and if it's already running then show a message and stop installation
-  if CheckForMutexes(installer_mutex_name) then begin
-    SuppressibleMsgBox(ExpandConstant('{cm:SetupIsRunningWarning}'), mbError, MB_OK, MB_OK);
+  if RegKeyExists(HKEY_LOCAL_MACHINE, 'SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\{#ConflictingAppId}_is1') or
+     RegKeyExists(HKEY_CURRENT_USER, 'SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\{#ConflictingAppId}_is1') then
+  begin
+    MsgBox('Detected conflicting application. Please, uninstall Seamly2D before proceeding installation.', mbError, MB_OK);
     Result := False;
   end
   else begin
-    Result := True;
-    CreateMutex(installer_mutex_name);
-  
-    ProgramRunningOnInstallMessage := ExpandConstant('{cm:WarnRunningOnUnInstall1}') + #13 + #13 + ExpandConstant('{cm:WarnRunningOnUnInstall2}');
-    InstallationCanceledMessage := ExpandConstant('{cm:WarnCancelInstall}');
-  
-    Result := PromptUntilProgramClosedOrInstallationCanceled( ProgramExeName1, ProgramName1 + ProgramRunningOnInstallMessage)
-    If Result Then
-    begin
-      Result := PromptUntilProgramClosedOrInstallationCanceled( ProgramExeName2, ProgramName2 + ProgramRunningOnInstallMessage)
-    end;
-  
-    if Not Result then
-    begin
-      MsgBox( InstallationCanceledMessage, mbInformation, MB_OK );
-    end else begin
-        Result := VersionCompareAndUninstall
+    // Create a mutex for the installer and if it's already running then show a message and stop installation
+    if CheckForMutexes(installer_mutex_name) then begin
+      SuppressibleMsgBox(ExpandConstant('{cm:SetupIsRunningWarning}'), mbError, MB_OK, MB_OK);
+      Result := False;
+    end
+    else begin
+      Result := True;
+      CreateMutex(installer_mutex_name);
+    
+      ProgramRunningOnInstallMessage := ExpandConstant('{cm:WarnRunningOnUnInstall1}') + #13 + #13 + ExpandConstant('{cm:WarnRunningOnUnInstall2}');
+      InstallationCanceledMessage := ExpandConstant('{cm:WarnCancelInstall}');
+    
+      Result := PromptUntilProgramClosedOrInstallationCanceled( ProgramExeName1, ProgramName1 + ProgramRunningOnInstallMessage)
+      If Result Then
+      begin
+        Result := PromptUntilProgramClosedOrInstallationCanceled( ProgramExeName2, ProgramName2 + ProgramRunningOnInstallMessage)
+      end;
+    
+      if Not Result then
+      begin
+        MsgBox( InstallationCanceledMessage, mbInformation, MB_OK );
+      end else begin
+          Result := VersionCompareAndUninstall
+      end;
     end;
   end;
 end;