--- a/configure.ac
+++ b/configure.ac
@@ -240,12 +240,13 @@
     else
 	if test -x "$with_python"
 	then
 	    echo Found python in $with_python
 	    PYTHON="$with_python"
 	else
+            AC_MSG_ERROR([Python not found; --with-python should be set to the python path])
             if test -x "$PYTHON"
             then
                 echo Found python in environment PYTHON=$PYTHON
                 with_python=`$PYTHON -c "import sys; print sys.exec_prefix"`
 	    else
 	        AC_PATH_PROG(PYTHON, python python2.4 python2.3 python2.2 python2.1 python2.0 python1.6 python1.5)
@@ -333,25 +334,25 @@
     if test "$LIBGCRYPT_CONFIG" != "no" ; then
       LIBGCRYPT_VERSION=`$LIBGCRYPT_CONFIG --version`
       if test VERSION_TO_NUMBER(echo $LIBGCRYPT_VERSION) -lt VERSION_TO_NUMBER(echo "1.1.42")
       then
         LIBGCRYPT_CFLAGS=""
         LIBGCRYPT_LIBS=""
-        echo 'gcrypt library version < 1.1.42 - Crypto extensions will not be available.'
+        AC_MSG_ERROR([gcrypt library version < 1.1.42 - this is an error])
       else
         LIBGCRYPT_CFLAGS=`$LIBGCRYPT_CONFIG $libgcrypt_config_args --cflags`
         LIBGCRYPT_LIBS=`$LIBGCRYPT_CONFIG $libgcrypt_config_args --libs`
         AC_DEFINE(HAVE_GCRYPT, 1, [Define if gcrypt library is available.])
         echo 'Crypto extensions will be available.'
         WITH_CRYPTO=1
         CRYPTO_TESTDIR=crypto
       fi
     else
       LIBGCRYPT_CFLAGS=""
       LIBGCRYPT_LIBS=""
-      echo 'Crypto extensions will not be available. Install libgcrypt and reconfigure to make available.'
+      AC_MSG_ERROR([libgcrypt not found - this is a bug in the vcpkg port])
     fi
 esac
 fi
 AC_SUBST(WITH_CRYPTO)
 AC_SUBST(CRYPTO_TESTDIR)
 AC_SUBST(LIBGCRYPT_CFLAGS)