diff --git a/src/include/isam.cpp b/src/include/isam.cpp
index 00c95888d..d92b4484f 100755
--- a/src/include/isam.cpp
+++ b/src/include/isam.cpp
@@ -2151,9 +2151,16 @@ int TSystemisamfile::update(
     {
       TRecnotype ni = 0L;     
       TFilename tmpfname; tmpfname.temp("tf");  
-      
+			err = open(_excllock);
+
+			if (err != NOERR)
+			{
+				error_box(FR("Non posso convertire %s errore n.ro %d"),
+					(const char*)filename(), err);
+				return err;
+			}
       err=DB_build(tmpfname, &wrec.rec());
-      
+			close();
       if (err != NOERR) 
       {
         err=get_error(err);