diff --git a/avogadro/io/fileformat.cpp b/avogadro/io/fileformat.cpp
index 95f26fa495..e993c56a17 100644
--- a/avogadro/io/fileformat.cpp
+++ b/avogadro/io/fileformat.cpp
@@ -63,7 +63,7 @@ bool FileFormat::open(const std::string& fileName_, Operation mode_)
   close();
   m_fileName = fileName_;
   m_mode = mode_;
-  if (!m_fileName.empty() && validateFileName(m_fileName)) {
+  if (!m_fileName.empty()) {
     // Imbue the standard C locale.
     locale cLocale("C");
     if (m_mode & Read) {
@@ -76,7 +76,7 @@ bool FileFormat::open(const std::string& fileName_, Operation mode_)
         appendError("Error opening file: " + fileName_);
         return false;
       }
-    } else if (m_mode & Write) {
+    } else if (m_mode & Write && validateFileName(m_fileName)) {
       auto* file = new ofstream(m_fileName.c_str(), std::ofstream::binary);
       m_out = file;
       if (file->is_open()) {
diff --git a/avogadro/qtgui/fileformatdialog.cpp b/avogadro/qtgui/fileformatdialog.cpp
index 16adfcee54..73765967ff 100644
--- a/avogadro/qtgui/fileformatdialog.cpp
+++ b/avogadro/qtgui/fileformatdialog.cpp
@@ -42,14 +42,6 @@ FileFormatDialog::FormatFilePair FileFormatDialog::fileToRead(
     if (fileName.isEmpty()) // user cancel
       return result;
 
-    if (FileFormat::validateFileName(fileName.toStdString()) == false) {
-      QMessageBox::warning(
-        parent, caption,
-        tr("The file name contains invalid characters. Please choose another "
-           "file name."));
-      continue;
-    }
-
     const Io::FileFormat* format = findFileFormat(
       parent, caption, fileName, FileFormat::File | FileFormat::Read);
 
@@ -94,6 +86,14 @@ FileFormatDialog::FormatFilePair FileFormatDialog::fileToWrite(
     if (fileName.isEmpty()) // user cancel
       return result;
 
+    if (FileFormat::validateFileName(fileName.toStdString()) == false) {
+      QMessageBox::warning(
+        parentWidget, caption,
+        tr("The file name contains invalid characters. Please choose another "
+           "file name."));
+      continue;
+    }
+
     const Io::FileFormat* format = findFileFormat(
       parentWidget, caption, fileName, FileFormat::File | FileFormat::Write);