diff --git a/include/boost/config/compiler/gcc.hpp b/include/boost/config/compiler/gcc.hpp
index 12958ab9..c67ab818 100644
--- a/include/boost/config/compiler/gcc.hpp
+++ b/include/boost/config/compiler/gcc.hpp
@@ -342,10 +342,10 @@
 #  error "Compiler not configured - please reconfigure"
 #endif
 //
-// last known and checked version is 4.9:
-#if (BOOST_GCC_VERSION > 40900)
+// last known and checked version is 7.1:
+#if (BOOST_GCC_VERSION > 70100)
 #  if defined(BOOST_ASSERT_CONFIG)
-#     error "Unknown compiler version - please run the configure tests and report the results"
+#     error "Boost.Config is older than your compiler - please check for an updated Boost release."
 #  else
 // we don't emit warnings here anymore since there are no defect macros defined for
 // gcc post 3.4, so any failures are gcc regressions...
diff --git a/include/boost/config/compiler/intel.hpp b/include/boost/config/compiler/intel.hpp
index f549dcb6..00396b03 100644
--- a/include/boost/config/compiler/intel.hpp
+++ b/include/boost/config/compiler/intel.hpp
@@ -551,7 +551,7 @@ template<> struct assert_intrinsic_wchar_t<unsigned short> {};
 // last known and checked version:
 #if (BOOST_INTEL_CXX_VERSION > 1700)
 #  if defined(BOOST_ASSERT_CONFIG)
-#     error "Unknown compiler version - please run the configure tests and report the results"
+#     error "Boost.Config is older than your compiler - please check for an updated Boost release."
 #  elif defined(_MSC_VER)
 //
 //      We don't emit this warning any more, since we have so few
diff --git a/include/boost/config/compiler/sunpro_cc.hpp b/include/boost/config/compiler/sunpro_cc.hpp
index 2453e7cf..56901840 100644
--- a/include/boost/config/compiler/sunpro_cc.hpp
+++ b/include/boost/config/compiler/sunpro_cc.hpp
@@ -203,8 +203,8 @@
 #endif
 //
 // last known and checked version is 0x590:
-#if (__SUNPRO_CC > 0x590)
+#if (__SUNPRO_CC > 0x5150)
 #  if defined(BOOST_ASSERT_CONFIG)
-#     error "Unknown compiler version - please run the configure tests and report the results"
+#     error "Boost.Config is older than your compiler - please check for an updated Boost release."
 #  endif
 #endif
diff --git a/include/boost/config/compiler/visualc.hpp b/include/boost/config/compiler/visualc.hpp
index c1cddf04..1a3f7824 100644
--- a/include/boost/config/compiler/visualc.hpp
+++ b/include/boost/config/compiler/visualc.hpp
@@ -324,8 +324,8 @@
 // last known and checked version is 19.11.25506 (VC++ 2017.3):
 #if (_MSC_VER > 1911)
 #  if defined(BOOST_ASSERT_CONFIG)
-#     error "Unknown compiler version - please run the configure tests and report the results"
-#  else
-#     pragma message("Unknown compiler version - please run the configure tests and report the results")
+#     error "Boost.Config is older than your current compiler version."
+#  elif !defined(BOOST_CONFIG_SUPPRESS_OUTDATED_MESSAGE)
+#     pragma message("Info: Boost.Config is older than your compiler version - probably nothing bad will happen - but you may wish to look for an update Boost version.  Define BOOST_CONFIG_SUPPRESS_OUTDATED_MESSAGE to suppress this message.")
 #  endif
 #endif