diff --git a/doc/examples/.DS_Store b/doc/examples/.DS_Store
deleted file mode 100644
index 488187a4..00000000
Binary files a/doc/examples/.DS_Store and /dev/null differ
diff --git a/src/classes/PRunDataHandler.cpp b/src/classes/PRunDataHandler.cpp
index 35a38583..5bd02d4e 100644
--- a/src/classes/PRunDataHandler.cpp
+++ b/src/classes/PRunDataHandler.cpp
@@ -3697,6 +3697,8 @@ Bool_t PRunDataHandler::ReadAsciiFile()
 {
   Bool_t success = true;
 
+std::cout << "as35> in ReadAsciiFile() ..." << std::endl;
+
   // open file
   std::ifstream f;
 
@@ -3848,7 +3850,14 @@ Bool_t PRunDataHandler::ReadAsciiFile()
           break;
         }
         ey = ostr->GetString().Atof();
+        if (ey == 0) {
+          std::cerr << std::endl << ">> PRunDataHandler::ReadAsciiFile **WARNING** line no " << lineNo << ": error y = 0 which doesn't make sense. Will set it to 1.0. Please check!!";
+          std::cerr << std::endl;
+          ey = 1.0;
+        }
       } else {
+        std::cerr << std::endl << ">> PRunDataHandler::ReadAsciiFile **WARNING** line no " << lineNo << ": error y = 0 which doesn't make sense. Will set it to 1.0. Please check!!";
+        std::cerr << std::endl;
         ey = 1.0;
       }
 
@@ -4357,7 +4366,7 @@ Bool_t PRunDataHandler::ReadDatFile()
   // open file
   std::ifstream f;
 
-  // open db-file
+  // open dat-file
   f.open(fRunPathName.Data(), std::ifstream::in);
   if (!f.is_open()) {
     std::cerr << std::endl << ">> PRunDataHandler::ReadDatFile **ERROR** Couldn't open data file (" << fRunPathName.Data() << ") for reading, sorry ...";
@@ -4456,6 +4465,12 @@ Bool_t PRunDataHandler::ReadDatFile()
           idx++;
         } else { // error value
           if (isData[i-1] == 1) { // Err or PosErr hence keep it
+            if (dval == 0.0) {
+              std::cout << std::endl << ">> PRunDataHandler::ReadDatFile **WARNING** found Err value = 0. Doesn't make sense! Will set it to 1. Please check!";
+              std::cerr << std::endl << ">>  in line: " << lineNo;
+              std::cerr << std::endl;
+              dval = 1.0;
+            }
             runData.fDataNonMusr.AppendSubErrData(idx-1, dval);
           }
         }
@@ -4470,11 +4485,11 @@ Bool_t PRunDataHandler::ReadDatFile()
 
   f.close();
 
-  // got through all the data sets and if there is NO error vector set it to '0.0'
+  // got through all the data sets and if there is NO error vector set it to '1.0'
   for (UInt_t i=0; i<noOfDataSets; i++) {
     if (runData.fDataNonMusr.GetErrData()->at(i).size() == 0) {
       for (UInt_t j=0; j<runData.fDataNonMusr.GetData()->at(i).size(); j++) {
-        runData.fDataNonMusr.AppendSubErrData(i, 0.0);
+        runData.fDataNonMusr.AppendSubErrData(i, 1.0);
       }
     }
   }