diff --git a/CHANGELOG.md b/CHANGELOG.md
index f3be0ce04112c2e8ccfcdb70d968fdc61543cca2..368cc84cfa9ca0a20e3fb7e010bc8c13d959e658 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -64,6 +64,7 @@ v4.3.4
   number of planes per process (!666)
 - Fix compilation with NEKTAR_USE_MESHGEN option
 - Fix IterativeFull solver in parallel (!685)
+- Fix error message for missing fld file (!689)
 
 **IncNavierStokesSolver:**
 - Fix 2nd order time-integration for VCSMapping (!687)
diff --git a/library/LibUtilities/BasicUtils/FieldIO.cpp b/library/LibUtilities/BasicUtils/FieldIO.cpp
index c676cd0fcb1830fbb99e63c89b44241849ff5dbe..7892213560036861045d0c8f6a45d7c7a12071e1 100644
--- a/library/LibUtilities/BasicUtils/FieldIO.cpp
+++ b/library/LibUtilities/BasicUtils/FieldIO.cpp
@@ -127,6 +127,7 @@ const std::string FieldIO::GetFileType(const std::string &filename,
             0x89, 0x48, 0x44, 0x46, 0x0d, 0x0a, 0x1a, 0x0a};
 
         std::ifstream datafile(datafilename.c_str(), ios_base::binary);
+        ASSERTL0(datafile.good(), "Unable to open file: " + filename);
 
         ioType = eHDF5;
         for (unsigned i = 0; i < 8 && datafile.good(); ++i)