diff --git a/util/dvsim/Deploy.py b/util/dvsim/Deploy.py
index 0a53397..7f958f4 100644
--- a/util/dvsim/Deploy.py
+++ b/util/dvsim/Deploy.py
@@ -174,13 +174,16 @@
                 self.odir_limiter(odir=self.odir)
             os.system("mkdir -p " + self.odir)
             # Dump all env variables for ease of debug.
-            with open(self.odir + "/env_vars", "w", encoding="UTF-8") as f:
+            with open(self.odir + "/env_vars",
+                      "w",
+                      encoding="UTF-8",
+                      errors="surrogateescape") as f:
                 for var in sorted(self.exports.keys()):
                     f.write("{}={}\n".format(var, self.exports[var]))
                 f.close()
             os.system("ln -s " + self.odir + " " + self.sim_cfg.links['D'] +
                       '/' + self.odir_ln)
-            f = open(self.log, "w", encoding="UTF-8")
+            f = open(self.log, "w", encoding="UTF-8", errors="surrogateescape")
             f.write("[Executing]:\n{}\n\n".format(self.cmd))
             f.flush()
             self.process = subprocess.Popen(args,