diff --git a/eos_download.py b/eos_download.py
index c6b8949..dfc5578 100644
--- a/eos_download.py
+++ b/eos_download.py
@@ -92,6 +92,7 @@
 import re
 import time
 import hashlib
+from random import randint
 
 # part of progress bar code
 def viewBar(a,b):
@@ -143,6 +144,29 @@ def md5(fname):
     return hash_md5.hexdigest()
 
 
+def getSession(accessToken, session_code_url="https://www.arista.com/custom_data/api/cvp/getSessionCode/"):
+   jsonpost = {'accessToken': accessToken}
+   result = requests.post(session_code_url, data=json.dumps(jsonpost))
+   if result.json()["status"]["message"] == 'Access token expired':
+      print("The API token has expired. Please visit arista.com, click on your profile and select Regenerate Token then re-run the script with the new token.")
+      sys.exit()
+   elif result.json()["status"]["message"] == 'Invalid access token':
+      print("The API token is incorrect. Please visit arista.com, click on your profile and check the Access Token. Then re-run the script with the correct token.")
+      sys.exit()
+   session_code = (result.json()["data"]["session_code"])
+   return(session_code)
+
+def jsonPost(url, token, data={}):
+   data['sessionCode'] = getSession(accessToken=creds)
+   result = requests.post(url, json.dumps(data))
+   i=0
+   while result.status_code != 200:
+      i +=1
+      print("Received HTTP status %s. Refreshing session and retrying (%s)." %(str(result.status_code), str(i)))
+      data['sessionCode'] = getSession(accessToken=creds)
+      result = requests.post(url, data)
+   return(result)
+
 # use argparse to take the user input, can fill in default values here if the user wishes
 # especially useful for the API key which won't change for a particular user
 warnings.filterwarnings("ignore")
@@ -184,23 +208,15 @@ def md5(fname):
 # the api key needs converting into base64 which outputs a byte value and then decoding to a string
 creds = (base64.b64encode(api.encode())).decode("utf-8")
 
-# there are 3 steps to downloading an image via the API, first is to get a session code
-session_code_url = "https://www.arista.com/custom_data/api/cvp/getSessionCode/"
-jsonpost = {'accessToken': creds}
-result = requests.post(session_code_url, data=json.dumps(jsonpost))
-if result.json()["status"]["message"] == 'Access token expired':
-   print("The API token has expired. Please visit arista.com, click on your profile and select Regenerate Token then re-run the script with the new token.")
-   sys.exit()
-elif result.json()["status"]["message"] == 'Invalid access token':
-   print("The API token is incorrect. Please visit arista.com, click on your profile and check the Access Token. Then re-run the script with the correct token.")
-   sys.exit()
-session_code = (result.json()["data"]["session_code"])
-
-# then get the current folder tree, similar to what you see on the download page in XML format
+# Get the current folder tree, similar to what you see on the download page in XML format
 folder_tree_url = "https://www.arista.com/custom_data/api/cvp/getFolderTree/"
-jsonpost = {'sessionCode': session_code}
-result = requests.post(folder_tree_url, data=json.dumps(jsonpost))
-folder_tree = (result.json()["data"]["xml"])
+result = jsonPost(url=folder_tree_url, token=creds)
+try:
+   folder_tree = (result.json()["data"]["xml"])
+except:
+   time.sleep(randint(1,10))
+   result = jsonPost(url=folder_tree_url, token=creds)
+   folder_tree = (result.json()["data"]["xml"])
 
 root = ET.fromstring(folder_tree)
 path = ""
@@ -216,7 +232,7 @@ def md5(fname):
          eos_filename = "EOS-2GB-" + image + "-INT.swi" # filename should be something like EOS-4.22.1F-INT.swi
          image = image.rstrip("-INT") # image should be 4.22.1F, need to remove the -INT
    elif "TerminAttr" in image: # if the user wants a TerminAttr image
-      z = 3 # corresponds to "CloudVision" top level folder
+      z = 2 # corresponds to "CloudVision" top level folder
       eos_filename = image + "-1.swix" # filename should be something like TerminAttr-1.7.4-1.swix
    elif "ipam" in img: # if the user wants a CVP IPAM image
       z = 2 # corresponds to "CloudVision" top level folder
@@ -328,32 +344,52 @@ def md5(fname):
          sys.exit()
       # the 3rd part of downloading a file is to use the path and session code to get the actual direct download link URL
       download_link_url = "https://www.arista.com/custom_data/api/cvp/getDownloadLink/"
-      jsonpost = {'sessionCode': session_code, 'filePath': path}
-      result = requests.post(download_link_url, data=json.dumps(jsonpost))
-      download_link = (result.json()["data"]["url"])         
+      jsonpost = {'filePath': path}
+      result = jsonPost(url=download_link_url, data=jsonpost, token=creds)
+      try:
+         download_link = (result.json()["data"]["url"])
+      except:
+         time.sleep(randint(1,10))
+         result = jsonPost(url=download_link_url, data=jsonpost, token=creds)
+         download_link = (result.json()["data"]["url"])
 
 
       print(eos_filename + " is currently downloading....")
       # download the file to the current folder
       download_file (download_link, eos_filename)
       if img == "ipam":  # for CVP IPAM there's 2 files to download so this grabs the 2nd file
-         jsonpost = {'sessionCode': session_code, 'filePath': path2}
-         result = requests.post(download_link_url, data=json.dumps(jsonpost))
-         download_link = (result.json()["data"]["url"])
+         jsonpost = {'filePath': path2}
+         result = jsonPost(url=download_link_url, data=jsonpost, token=creds)
+         try:
+            download_link = (result.json()["data"]["url"])
+         except:
+            time.sleep(randint(1,10))
+            result = jsonPost(url=download_link_url, data=jsonpost, token=creds)
+            download_link = (result.json()["data"]["url"])
          print(ipam_filename + " is currently downloading....")  
          download_file(download_link, ipam_filename)
       elif img == "cloudbuilder":  # for CVP CloudBuilder there's 2 files to download so this grabs the 2nd file
-         jsonpost = {'sessionCode': session_code, 'filePath': path2}
-         result = requests.post(download_link_url, data=json.dumps(jsonpost))
-         download_link = (result.json()["data"]["url"])
+         jsonpost = {'filePath': path2}
+         result = jsonPost(url=download_link_url, data=jsonpost, token=creds)
+         try:
+            download_link = (result.json()["data"]["url"])
+         except:
+            time.sleep(randint(1,10))
+            result = jsonPost(url=download_link_url, data=jsonpost, token=creds)
+            download_link = (result.json()["data"]["url"])
          print(cb_filename + " is currently downloading....")  
          download_file(download_link, cb_filename)
 
 
       if (img != 'source') and (img != 'RN'):
-         jsonpost = {'sessionCode': session_code, 'filePath': sha512_path}
-         sha512_result = requests.post(download_link_url, data=json.dumps(jsonpost))
-         sha512_download_link = (sha512_result.json()["data"]["url"])
+         jsonpost = {'filePath': sha512_path}
+         sha512_result = jsonPost(url=download_link_url, data=jsonpost, token=creds)
+         try:
+            sha512_download_link = (sha512_result.json()["data"]["url"])
+         except:
+            time.sleep(randint(1,10))
+            sha512_result = jsonPost(url=download_link_url, data=jsonpost, token=creds)
+            sha512_download_link = (sha512_result.json()["data"]["url"])
          if "TerminAttr" in image:
             download_file (sha512_download_link, eos_filename + '.md5sum')
          if "cvp" in image:
@@ -364,17 +400,27 @@ def md5(fname):
             sha512_file = line
 
          if img == "ipam":
-            jsonpost = {'sessionCode': session_code, 'filePath': sha512_path2}
-            sha512_result = requests.post(download_link_url, data=json.dumps(jsonpost))
-            sha512_download_link = (sha512_result.json()["data"]["url"])
+            jsonpost = {'filePath': sha512_path2}
+            sha512_result = jsonPost(url=download_link_url, data=jsonpost, token=creds)
+            try:
+               sha512_download_link = (sha512_result.json()["data"]["url"])
+            except:
+               time.sleep(randint(1,10))
+               sha512_result = jsonPost(url=download_link_url, data=jsonpost, token=creds)
+               sha512_download_link = (sha512_result.json()["data"]["url"])
             download_file (sha512_download_link, ipam_filename + '.sha512sum')
             for line in urllib.request.urlopen(sha512_download_link):
                sha512_file2 = line
       
          if img == "cloudbuilder":
-            jsonpost = {'sessionCode': session_code, 'filePath': sha512_path2}
-            sha512_result = requests.post(download_link_url, data=json.dumps(jsonpost))
-            sha512_download_link = (sha512_result.json()["data"]["url"])
+            jsonpost = {'filePath': sha512_path2}
+            sha512_result = jsonPost(url=download_link_url, data=jsonpost, token=creds)
+            try:
+               sha512_download_link = (sha512_result.json()["data"]["url"])
+            except:
+               time.sleep(randint(1,10))
+               sha512_result = jsonPost(url=download_link_url, data=jsonpost, token=creds)
+               sha512_download_link = (sha512_result.json()["data"]["url"])
             download_file (sha512_download_link, cb_filename + '.sha512sum')
             for line in urllib.request.urlopen(sha512_download_link):
                sha512_file2 = line
@@ -417,7 +463,7 @@ def md5(fname):
          eos_filename = filename
          eos_bundle = image
       elif "TerminAttr" in image:
-         z = 3
+         z = 2
          filename = image + "-1.swix"
          terminattr_filename = filename
       else: