diff --git a/kcms/kfontinst/kio/KioFonts.cpp b/kcms/kfontinst/kio/KioFonts.cpp
index ea8e99df1..8e90cacbe 100644
--- a/kcms/kfontinst/kio/KioFonts.cpp
+++ b/kcms/kfontinst/kio/KioFonts.cpp
@@ -27,6 +27,7 @@
 #include <pwd.h>
 #include <sys/stat.h>
 #include <unistd.h>
+#include <kio_version.h>
 
 static constexpr int s_MAX_IPC_SIZE = 1024 * 32;
 
@@ -202,7 +203,15 @@ void CKioFonts::put(const QUrl &url, int /*permissions*/, KIO::JobFlags /*flags*
     qCDebug(KCM_KFONTINST_KIO) << url;
     QStringList pathList(url.adjusted(QUrl::StripTrailingSlash).path().split(QLatin1Char('/'), Qt::SkipEmptyParts));
     EFolder folder(getFolder(pathList));
-
+#if KIO_VERSION >= QT_VERSION_CHECK(5, 96, 0)
+    if (!Misc::root() && FOLDER_ROOT == folder) {
+        error(KIO::ERR_WORKER_DEFINED, i18n("Can only install fonts to either \"%1\" or \"%2\".", KFI_KIO_FONTS_USER.toString(), KFI_KIO_FONTS_SYS.toString()));
+    } else if (Misc::isPackage(url.fileName())) {
+        error(KIO::ERR_WORKER_DEFINED,
+              i18n("You cannot install a fonts package directly.\n"
+                   "Please extract %1, and install the components individually.",
+                   url.toDisplayString()));
+#else
     if (!Misc::root() && FOLDER_ROOT == folder) {
         error(KIO::ERR_SLAVE_DEFINED, i18n("Can only install fonts to either \"%1\" or \"%2\".", KFI_KIO_FONTS_USER.toString(), KFI_KIO_FONTS_SYS.toString()));
     } else if (Misc::isPackage(url.fileName())) {
@@ -210,6 +219,7 @@ void CKioFonts::put(const QUrl &url, int /*permissions*/, KIO::JobFlags /*flags*
               i18n("You cannot install a fonts package directly.\n"
                    "Please extract %1, and install the components individually.",
                    url.toDisplayString()));
+#endif
     } else {
         if (!m_tempDir) {
             m_tempDir = new QTemporaryDir(QDir::tempPath() + QString::fromLatin1("/kio_fonts_") + QString::number(getpid()));
@@ -435,12 +445,20 @@ void CKioFonts::get(const QUrl &url)
 
 void CKioFonts::copy(const QUrl &, const QUrl &, int, KIO::JobFlags)
 {
+#if KIO_VERSION >= QT_VERSION_CHECK(5, 96, 0)
+    error(KIO::ERR_WORKER_DEFINED, i18n("Cannot copy fonts"));
+#else
     error(KIO::ERR_SLAVE_DEFINED, i18n("Cannot copy fonts"));
+#endif
 }
 
 void CKioFonts::rename(const QUrl &, const QUrl &, KIO::JobFlags)
 {
+#if KIO_VERSION >= QT_VERSION_CHECK(5, 96, 0)
+    error(KIO::ERR_WORKER_DEFINED, i18n("Cannot move fonts"));
+#else
     error(KIO::ERR_SLAVE_DEFINED, i18n("Cannot move fonts"));
+#endif
 }
 
 void CKioFonts::del(const QUrl &url, bool isFile)
@@ -450,10 +468,17 @@ void CKioFonts::del(const QUrl &url, bool isFile)
     EFolder folder(getFolder(pathList));
     QString name(removeKnownExtension(url));
 
+#if KIO_VERSION >= QT_VERSION_CHECK(5, 96, 0)
+    if (!isFile) {
+        error(KIO::ERR_WORKER_DEFINED, i18n("Only fonts may be deleted."));
+    } else if (!Misc::root() && FOLDER_ROOT == folder) {
+        error(KIO::ERR_WORKER_DEFINED, i18n("Can only remove fonts from either \"%1\" or \"%2\".", KFI_KIO_FONTS_USER.toString(), KFI_KIO_FONTS_SYS.toString()));
+#else
     if (!isFile) {
         error(KIO::ERR_SLAVE_DEFINED, i18n("Only fonts may be deleted."));
     } else if (!Misc::root() && FOLDER_ROOT == folder) {
         error(KIO::ERR_SLAVE_DEFINED, i18n("Can only remove fonts from either \"%1\" or \"%2\".", KFI_KIO_FONTS_USER.toString(), KFI_KIO_FONTS_SYS.toString()));
+#endif
     } else if (!name.isEmpty()) {
         handleResp(m_interface->uninstall(name, Misc::root() || FOLDER_SYS == folder), name);
     } else {
@@ -480,7 +505,11 @@ void CKioFonts::stat(const QUrl &url)
         } else if (FOLDER_SYS == folder || FOLDER_USER == folder) {
             createUDSEntry(entry, folder);
         } else {
+#if KIO_VERSION >= QT_VERSION_CHECK(5, 96, 0)
+            error(KIO::ERR_WORKER_DEFINED, i18n("Please specify \"%1\" or \"%2\".", KFI_KIO_FONTS_USER.toString(), KFI_KIO_FONTS_SYS.toString()));
+#else
             error(KIO::ERR_SLAVE_DEFINED, i18n("Please specify \"%1\" or \"%2\".", KFI_KIO_FONTS_USER.toString(), KFI_KIO_FONTS_SYS.toString()));
+#endif
             return;
         }
         break;
@@ -702,6 +731,31 @@ Family CKioFonts::getFont(const QUrl &url, EFolder folder)
 void CKioFonts::handleResp(int resp, const QString &file, const QString &tempFile, bool destIsSystem)
 {
     switch (resp) {
+#if KIO_VERSION >= QT_VERSION_CHECK(5, 96, 0)
+    case FontInst::STATUS_NO_SYS_CONNECTION:
+        error(KIO::ERR_WORKER_DEFINED, i18n("Failed to start the system daemon"));
+        break;
+    case FontInst::STATUS_SERVICE_DIED:
+        error(KIO::ERR_WORKER_DEFINED, i18n("Backend died"));
+        break;
+    case FontInst::STATUS_BITMAPS_DISABLED:
+        error(KIO::ERR_WORKER_DEFINED, i18n("%1 is a bitmap font, and these have been disabled on your system.", file));
+        break;
+    case FontInst::STATUS_ALREADY_INSTALLED:
+        error(KIO::ERR_WORKER_DEFINED, i18n("%1 contains the font <b>%2</b>, which is already installed on your system.", file, FC::getName(tempFile)));
+        break;
+    case FontInst::STATUS_NOT_FONT_FILE:
+        error(KIO::ERR_WORKER_DEFINED, i18n("%1 is not a font.", file));
+        break;
+    case FontInst::STATUS_PARTIAL_DELETE:
+        error(KIO::ERR_WORKER_DEFINED, i18n("Could not remove all files associated with %1", file));
+        break;
+    case KIO::ERR_FILE_ALREADY_EXIST: {
+        QString name(Misc::modifyName(file)), destFolder(Misc::getDestFolder(m_interface->folderName(destIsSystem), name));
+        error(KIO::ERR_WORKER_DEFINED, i18n("<i>%1</i> already exists.", destFolder + name));
+        break;
+    }
+#else
     case FontInst::STATUS_NO_SYS_CONNECTION:
         error(KIO::ERR_SLAVE_DEFINED, i18n("Failed to start the system daemon"));
         break;
@@ -725,6 +779,7 @@ void CKioFonts::handleResp(int resp, const QString &file, const QString &tempFil
         error(KIO::ERR_SLAVE_DEFINED, i18n("<i>%1</i> already exists.", destFolder + name));
         break;
     }
+#endif
     case FontInst::STATUS_OK:
         finished();
         break;
diff --git a/kioslave/applications/kio_applications.cpp b/kioslave/applications/kio_applications.cpp
index 119fe3797..6a4b60ca2 100644
--- a/kioslave/applications/kio_applications.cpp
+++ b/kioslave/applications/kio_applications.cpp
@@ -13,6 +13,7 @@
 
 #include <QStandardPaths>
 #include <QUrl>
+#include <kio_version.h>
 
 // Pseudo plugin class to embed meta data
 class KIOPluginForMetaData : public QObject
@@ -127,7 +128,12 @@ void ApplicationsProtocol::stat(const QUrl &url)
         if (service && service->isValid()) {
             createFileEntry(entry, service, url);
         } else {
+
+#if KIO_VERSION >= QT_VERSION_CHECK(5, 96, 0)
+            error(KIO::ERR_WORKER_DEFINED, i18n("Unknown application folder"));
+#else
             error(KIO::ERR_SLAVE_DEFINED, i18n("Unknown application folder"));
+#endif
             return;
         }
     }