After launching iot-server.bat on Windows, try to log in as any valid user and "Authentication Error" is seen on browser.

The console shows

Exception in Authentication Framework
java.lang.NoClassDefFoundError: org/apache/commons/lang/StringUtils

Ref: https://wso2.org/jira/browse/ANLYEXT-5

This is resolved by fixing the path for commons-lang*.jar

modules/distribution/src/core/bin/iot-server.bat

@@ -70,7 +70,7 @@ FOR %%C in ("%CARBON_HOME%\bin\*.jar") DO set CARBON_CLASSPATH=!CARBON_CLASSPATH
 
 set CARBON_CLASSPATH="%JAVA_HOME%\lib\tools.jar";%CARBON_CLASSPATH%;
 
-FOR %%D in ("%CARBON_HOME%\wso2\lib\commons-lang*.jar") DO set CARBON_CLASSPATH=!CARBON_CLASSPATH!;".\lib\%%~nD%%~xD"
+FOR %%D in ("%CARBON_HOME%\wso2\lib\commons-lang*.jar") DO set CARBON_CLASSPATH=!CARBON_CLASSPATH!;".\wso2\lib\%%~nD%%~xD"
 
 rem ----- Process the input command -------------------------------------------
 

modules/distribution/src/core/resources/profiles/backend/iot-server.bat

@@ -70,7 +70,7 @@ FOR %%C in ("%CARBON_HOME%\bin\*.jar") DO set CARBON_CLASSPATH=!CARBON_CLASSPATH
 
 set CARBON_CLASSPATH="%JAVA_HOME%\lib\tools.jar";%CARBON_CLASSPATH%;
 
-FOR %%D in ("%CARBON_HOME%\wso2\lib\commons-lang*.jar") DO set CARBON_CLASSPATH=!CARBON_CLASSPATH!;".\lib\%%~nD%%~xD"
+FOR %%D in ("%CARBON_HOME%\wso2\lib\commons-lang*.jar") DO set CARBON_CLASSPATH=!CARBON_CLASSPATH!;".\wso2\lib\%%~nD%%~xD"
 
 rem ----- Process the input command -------------------------------------------
 

modules/distribution/src/core/resources/profiles/keymanager/iot-server.bat

@@ -70,7 +70,7 @@ FOR %%C in ("%CARBON_HOME%\bin\*.jar") DO set CARBON_CLASSPATH=!CARBON_CLASSPATH
 
 set CARBON_CLASSPATH="%JAVA_HOME%\lib\tools.jar";%CARBON_CLASSPATH%;
 
-FOR %%D in ("%CARBON_HOME%\wso2\lib\commons-lang*.jar") DO set CARBON_CLASSPATH=!CARBON_CLASSPATH!;".\lib\%%~nD%%~xD"
+FOR %%D in ("%CARBON_HOME%\wso2\lib\commons-lang*.jar") DO set CARBON_CLASSPATH=!CARBON_CLASSPATH!;".\wso2\lib\%%~nD%%~xD"
 
 rem ----- Process the input command -------------------------------------------
 

modules/distribution/src/core/resources/profiles/manager/iot-server.bat

@@ -70,7 +70,7 @@ FOR %%C in ("%CARBON_HOME%\bin\*.jar") DO set CARBON_CLASSPATH=!CARBON_CLASSPATH
 
 set CARBON_CLASSPATH="%JAVA_HOME%\lib\tools.jar";%CARBON_CLASSPATH%;
 
-FOR %%D in ("%CARBON_HOME%\wso2\lib\commons-lang*.jar") DO set CARBON_CLASSPATH=!CARBON_CLASSPATH!;".\lib\%%~nD%%~xD"
+FOR %%D in ("%CARBON_HOME%\wso2\lib\commons-lang*.jar") DO set CARBON_CLASSPATH=!CARBON_CLASSPATH!;".\wso2\lib\%%~nD%%~xD"
 
 rem ----- Process the input command -------------------------------------------