diff --git a/reg_tests/executeAerodiskRegressionCase.py b/reg_tests/executeAerodiskRegressionCase.py
index ae1dcd5eec..06b8624c88 100644
--- a/reg_tests/executeAerodiskRegressionCase.py
+++ b/reg_tests/executeAerodiskRegressionCase.py
@@ -88,7 +88,8 @@
 if not os.path.isdir(inputsDirectory):
     rtl.exitWithError("The test data inputs directory, {}, does not exist. Verify your local repository is up to date.".format(inputsDirectory))
 
-rtl.copyTree(inputsDirectory, testBuildDirectory, renameDict={'adsk_driver.outb':'adsk_driver_ref.outb'})
+if not os.path.isdir(testBuildDirectory):
+    rtl.copyTree(inputsDirectory, testBuildDirectory, renameDict={'adsk_driver.outb':'adsk_driver_ref.outb'})
 
 ### Run aerodisk on the test case
 if not noExec:
diff --git a/reg_tests/executeAerodynPyRegressionCase.py b/reg_tests/executeAerodynPyRegressionCase.py
index e9de4f3bb0..66bcb3c233 100644
--- a/reg_tests/executeAerodynPyRegressionCase.py
+++ b/reg_tests/executeAerodynPyRegressionCase.py
@@ -90,7 +90,8 @@
 
 
 # create the local output directory and initialize it with input files 
-rtl.copyTree(inputsDirectory, testBuildDirectory, renameDict={'py_ad_driver.out':'py_ad_driver_ref.out'})
+if not os.path.isdir(testBuildDirectory):
+    rtl.copyTree(inputsDirectory, testBuildDirectory, renameDict={'py_ad_driver.out':'py_ad_driver_ref.out'})
        # , excludeExt=['.out','.outb'])
 
 ### Run aerodyn on the test case
diff --git a/reg_tests/executeAerodynRegressionCase.py b/reg_tests/executeAerodynRegressionCase.py
index 3c6cbeac8f..30fe3c2b90 100644
--- a/reg_tests/executeAerodynRegressionCase.py
+++ b/reg_tests/executeAerodynRegressionCase.py
@@ -92,16 +92,12 @@
 # Special case, copy the BAR Baseline files
 dst = os.path.join(buildDirectory, "BAR_Baseline")
 src = os.path.join(moduleDirectory, "BAR_Baseline")
-try:
+if not os.path.isdir(dst):
     rtl.copyTree(src, dst)
-except:
-    # This can fail if two processes are copying the file at the same time
-    print('>>> Copy failed')
-    import time
-    time.sleep(1)
 
 # create the local output directory and initialize it with input files 
-rtl.copyTree(inputsDirectory, testBuildDirectory, renameDict={'ad_driver.outb':'ad_driver_ref.outb'})
+if not os.path.isdir(testBuildDirectory):
+    rtl.copyTree(inputsDirectory, testBuildDirectory, renameDict={'ad_driver.outb':'ad_driver_ref.outb'})
        # , excludeExt=['.out','.outb'])
 
 ### Run aerodyn on the test case
diff --git a/reg_tests/executeHydrodynPyRegressionCase.py b/reg_tests/executeHydrodynPyRegressionCase.py
index 56cf5a8bf3..d121932b6f 100644
--- a/reg_tests/executeHydrodynPyRegressionCase.py
+++ b/reg_tests/executeHydrodynPyRegressionCase.py
@@ -90,7 +90,8 @@
 
     
 # create the local output directory and initialize it with input files 
-rtl.copyTree(inputsDirectory, testBuildDirectory)
+if not os.path.isdir(testBuildDirectory):
+    rtl.copyTree(inputsDirectory, testBuildDirectory)
        # , excludeExt=['.out','.outb'])
 
 ### Run HydroDyn on the test case
diff --git a/reg_tests/executeMoordynPyRegressionCase.py b/reg_tests/executeMoordynPyRegressionCase.py
index 0f43de1e66..912d90d2fd 100644
--- a/reg_tests/executeMoordynPyRegressionCase.py
+++ b/reg_tests/executeMoordynPyRegressionCase.py
@@ -90,7 +90,8 @@
     rtl.exitWithError("The test data inputs directory, {}, does not exist. Verify your local repository is up to date.".format(inputsDirectory))
 
 # create the local output directory and initialize it with input files 
-rtl.copyTree(inputsDirectory, testBuildDirectory, renameDict={'MD.out':'MD_ref.out','MDroot.MD.out':'MDroot.MD_ref.out'})
+if not os.path.isdir(testBuildDirectory):
+    rtl.copyTree(inputsDirectory, testBuildDirectory, renameDict={'MD.out':'MD_ref.out','MDroot.MD.out':'MDroot.MD_ref.out'})
        # , excludeExt=['.out','.outb'])
 
 ### Run MoorDyn on the test case
diff --git a/reg_tests/executeOpenfastLinearRegressionCase.py b/reg_tests/executeOpenfastLinearRegressionCase.py
index 91f43062b3..c5bb641041 100644
--- a/reg_tests/executeOpenfastLinearRegressionCase.py
+++ b/reg_tests/executeOpenfastLinearRegressionCase.py
@@ -163,8 +163,8 @@ def indent(msg, sindent='\t'):
             shutil.copy2(srcname, dstname)
 # 
 # Copying the actual test directory
-# if not os.path.isdir(testBuildDirectory):
-rtl.copyTree(inputsDirectory, testBuildDirectory, excludeExt=excludeExt, renameExtDict={'.lin':'.ref_lin'})
+if not os.path.isdir(testBuildDirectory):
+    rtl.copyTree(inputsDirectory, testBuildDirectory, excludeExt=excludeExt, renameExtDict={'.lin':'.ref_lin'})
 
 ### Run openfast on the test case
 if not noExec:
diff --git a/reg_tests/executeSimpleElastodynRegressionCase.py b/reg_tests/executeSimpleElastodynRegressionCase.py
index e271872574..a5232038b4 100644
--- a/reg_tests/executeSimpleElastodynRegressionCase.py
+++ b/reg_tests/executeSimpleElastodynRegressionCase.py
@@ -88,7 +88,8 @@
 if not os.path.isdir(inputsDirectory):
     rtl.exitWithError("The test data inputs directory, {}, does not exist. Verify your local repository is up to date.".format(inputsDirectory))
 
-rtl.copyTree(inputsDirectory, testBuildDirectory, renameDict={'sed_driver.outb':'sed_driver_ref.outb'})
+if not os.path.isdir(testBuildDirectory):
+    rtl.copyTree(inputsDirectory, testBuildDirectory, renameDict={'sed_driver.outb':'sed_driver_ref.outb'})
 
 ### Run SED on the test case
 if not noExec:
diff --git a/reg_tests/executeSubdynRegressionCase.py b/reg_tests/executeSubdynRegressionCase.py
index 04363472d4..ef96940713 100644
--- a/reg_tests/executeSubdynRegressionCase.py
+++ b/reg_tests/executeSubdynRegressionCase.py
@@ -89,7 +89,8 @@
     rtl.exitWithError("The test data inputs directory, {}, does not exist. Verify your local repository is up to date.".format(inputsDirectory))
 
 # create the local output directory and initialize it with input files (overwrite if exists)
-rtl.copyTree(inputsDirectory, testBuildDirectory, renameExtDict={'.out':'_ref.out'}, includeExt=['.dvr','.dat','.out','.csv'])
+if not os.path.isdir(testBuildDirectory):
+    rtl.copyTree(inputsDirectory, testBuildDirectory, renameExtDict={'.out':'_ref.out'}, includeExt=['.dvr','.dat','.out','.csv'])
 
 
 ### Run SubDyn on the test case
diff --git a/reg_tests/executeUnsteadyAeroRegressionCase.py b/reg_tests/executeUnsteadyAeroRegressionCase.py
index 53c8bf567e..94a11e613f 100644
--- a/reg_tests/executeUnsteadyAeroRegressionCase.py
+++ b/reg_tests/executeUnsteadyAeroRegressionCase.py
@@ -92,7 +92,8 @@
 # create the local output directory and initialize it with input files 
 renameDict={'UA'+str(i)+'.outb':'UA'+str(i)+'_ref.outb' for i in [2,3,4,5,6,7]}
 
-rtl.copyTree(inputsDirectory, testBuildDirectory, renameDict=renameDict
+if not os.path.isdir(testBuildDirectory):
+    rtl.copyTree(inputsDirectory, testBuildDirectory, renameDict=renameDict
        , excludeExt=['.sum'])
        # , excludeExt=['.out','.outb','.sum'])