diff --git a/typo3/sysext/install/Classes/Controller/Action/Ajax/ExtensionScannerFiles.php b/typo3/sysext/install/Classes/Controller/Action/Ajax/ExtensionScannerFiles.php
index f6c532134771177e3a1052fff5db08b13cfd8700..e460b02a88c2236d83cec5cd7c9a29381f4eeb2c 100644
--- a/typo3/sysext/install/Classes/Controller/Action/Ajax/ExtensionScannerFiles.php
+++ b/typo3/sysext/install/Classes/Controller/Action/Ajax/ExtensionScannerFiles.php
@@ -54,7 +54,7 @@ class ExtensionScannerFiles extends AbstractAjaxAction
         $relativeFileNames = [];
         foreach ($files as $file) {
             /** @var $file SplFileInfo */
-            $relativeFileNames[] = $file->getRelativePathname();
+            $relativeFileNames[] = GeneralUtility::fixWindowsFilePath($file->getRelativePathname());
         }
 
         $this->view->assignMultiple([
diff --git a/typo3/sysext/install/Classes/Controller/Action/Ajax/ExtensionScannerMarkFullyScannedRestFiles.php b/typo3/sysext/install/Classes/Controller/Action/Ajax/ExtensionScannerMarkFullyScannedRestFiles.php
index 6d86966188a57f44d9859575f5f7f1010ca901fd..be5f41350fd6a85b23af7981897c60736bee6128 100644
--- a/typo3/sysext/install/Classes/Controller/Action/Ajax/ExtensionScannerMarkFullyScannedRestFiles.php
+++ b/typo3/sysext/install/Classes/Controller/Action/Ajax/ExtensionScannerMarkFullyScannedRestFiles.php
@@ -57,7 +57,7 @@ class ExtensionScannerMarkFullyScannedRestFiles extends AbstractAjaxAction
             }
 
             // Build array of file (hashes) not affected by current scan, if they are tagged as "FullyScanned"
-            $parsedRestFile = array_pop($documentationFile->getListEntry(realpath($restFile->getPathname())));
+            $parsedRestFile = array_pop($documentationFile->getListEntry(strtr(realpath($restFile->getPathname()), '\\', '/')));
             if (!in_array($parsedRestFile['file_hash'], $foundRestFileHashes, true)
                 && in_array('FullyScanned', $parsedRestFile['tags'], true)
             ) {
diff --git a/typo3/sysext/install/Classes/Controller/Action/Ajax/ExtensionScannerScanFile.php b/typo3/sysext/install/Classes/Controller/Action/Ajax/ExtensionScannerScanFile.php
index 09120f6a8e0f2ff908134b4773bc57947a94fe4b..2f8f39909d4db32cd9fce692a4f0ac3ed4a953a1 100644
--- a/typo3/sysext/install/Classes/Controller/Action/Ajax/ExtensionScannerScanFile.php
+++ b/typo3/sysext/install/Classes/Controller/Action/Ajax/ExtensionScannerScanFile.php
@@ -201,7 +201,7 @@ class ExtensionScannerScanFile extends AbstractAjaxAction
                     $restFileLocation = $restFile->getPathname();
                     break;
                 }
-                $parsedRestFile = array_pop($documentationFile->getListEntry(realpath($restFileLocation)));
+                $parsedRestFile = array_pop($documentationFile->getListEntry(strtr(realpath($restFileLocation), '\\', '/')));
                 $version = GeneralUtility::trimExplode('/', $restFileLocation);
                 array_pop($version);
                 // something like "8.2" .. "8.7" .. "master"