diff --git a/doc/FAQ.html b/doc/FAQ.html
index c4aeae9f..9d4ee220 100644
--- a/doc/FAQ.html
+++ b/doc/FAQ.html
@@ -46,6 +46,7 @@ a:visited { color: #0000EE; }
 <li><a href="#3ffe490e">Why do I get the error 'The procedure entry point De/EncodePointer could not be located' on startup?</a>
 <li><a href="#01922741">Why do I get the error 'LameXP.exe is not a valid Win32 application' on startup?</a>
 <li><a href="#491aaad9">Why do I get the error 'A device attached to the system is not functioning' on startup?</a>
+<li><a href="#a0fd5ae8">Why do I get the error 'File &acute;tool_foobar.exe&acute; could not be locked!' on startup?</a>
 <li><a href="#f35cfa24">How can I translate LameXP to my language or improve an existing translation?</a>
 <li><a href="#8dba381f">Where can I download the latest version of LameXP?</a>
 <li><a href="#9c2e273d">Where can I submit bug reports or feature requests?</a>
@@ -565,6 +566,21 @@ Remark: Executables compiled with Microsoft Visual Studio 2010 won't run on Wind
 
 <br><br>
 
+<a name="a0fd5ae8"></a><b>Why do I get the error 'File &acute;tool_foobar.exe&acute; could not be locked!' on startup?</b><br>
+<br>
+This error indicates that LameXP was unable to open/read a required file - one that it just has extracted<br>
+itself. Generally this should never happen, but we have reports that some bogus "anti-vrius" software might<br>
+trigger this kind of errors. Of course there is nothing we can do on our side, if the error is induced by<br>
+proprietary third-party software (such as faulty "anti-virus" software). So please try to temporarily(!)<br>
+uninstall/disable your anti-virus software. If the problem goes away, you can be sure it was caused by the<br>
+anti-virus software. In that case report the bug to the support team of your anti-virus software as soon as<br>
+possible. Or, if they don't fix the bug (in due time), switch to a better anti-virus product!<br>
+<br>
+See also:<br>
+<a href="#96205e91">My anti-virus program raises an alarm when I try to download/install/launch LameXP. Why is that?</a><br><br>
+
+<br><br>
+
 <a name="f35cfa24"></a><b>How can I translate LameXP to my language or improve an existing translation?</b><br>
 <br>
 Please see the guide for translators at:<br><ul>
diff --git a/src/Config.h b/src/Config.h
index 11ebdb21..689fd034 100644
--- a/src/Config.h
+++ b/src/Config.h
@@ -27,10 +27,10 @@
 
 #define VER_LAMEXP_MAJOR					4
 #define VER_LAMEXP_MINOR_HI					0
-#define VER_LAMEXP_MINOR_LO					2
-#define VER_LAMEXP_TYPE						Final
+#define VER_LAMEXP_MINOR_LO					3
+#define VER_LAMEXP_TYPE						Alpha
 #define VER_LAMEXP_PATCH					1
-#define VER_LAMEXP_BUILD					578
+#define VER_LAMEXP_BUILD					579
 
 ///////////////////////////////////////////////////////////////////////////////
 // Tools versions
diff --git a/src/LockedFile.cpp b/src/LockedFile.cpp
index 53773ed4..8a7f3c5b 100644
--- a/src/LockedFile.cpp
+++ b/src/LockedFile.cpp
@@ -57,10 +57,16 @@ LockedFile::LockedFile(const QString &resourcePath, const QString &outPath, cons
 		throw error_msg;
 	}
 
-	//Now lock the file
-	m_fileHandle = CreateFileW(QWCHAR(QDir::toNativeSeparators(m_filePath)), GENERIC_READ, FILE_SHARE_READ, NULL, OPEN_EXISTING, NULL, NULL);
-
-	if(m_fileHandle == INVALID_HANDLE_VALUE)
+	//Now lock the file!
+	for(int i = 0; i < 1000; i++)
+	{
+		if((m_fileHandle = CreateFileW(QWCHAR(QDir::toNativeSeparators(m_filePath)), GENERIC_READ, FILE_SHARE_READ, NULL, OPEN_EXISTING, NULL, NULL)) != INVALID_HANDLE_VALUE)
+		{
+			break;
+		}
+		Sleep(100);
+	}
+	if((m_fileHandle == NULL) || (m_fileHandle == INVALID_HANDLE_VALUE))
 	{
 		QFile::remove(QFileInfo(outFile).canonicalFilePath());
 		char error_msg[512];
@@ -76,6 +82,13 @@ LockedFile::LockedFile(const QString &resourcePath, const QString &outPath, cons
 		fileHash.addData(outFile.readAll());
 		outFile.close();
 	}
+	else
+	{
+		QFile::remove(QFileInfo(outFile).canonicalFilePath());
+		char error_msg[512];
+		strcpy_s(error_msg, 512, QString("File '%1' could not be read!").arg(QFileInfo(outFile).fileName()).toLatin1().constData());
+		throw error_msg;
+	}
 
 	//Compare hashes
 	if(_stricmp(fileHash.result().toHex().constData(), expectedHash.constData()))