diff --git a/.github/workflows/DevelopmentDPC.yml b/.github/workflows/DevelopmentDPC.yml
index 26190ec..3f70424 100644
--- a/.github/workflows/DevelopmentDPC.yml
+++ b/.github/workflows/DevelopmentDPC.yml
@@ -7,9 +7,11 @@ name: Development DPC
 
 on:
   push:
-    branches: [ "Development" ]
+    branches-ignore:
+      - main
   pull_request:
-    branches: [ "Development" ]
+    branches-ignore:
+      - main
 
 jobs:
   build:
diff --git a/DPCLibrary/Utils/Validate.cs b/DPCLibrary/Utils/Validate.cs
index 8bf3396..7ab08cf 100644
--- a/DPCLibrary/Utils/Validate.cs
+++ b/DPCLibrary/Utils/Validate.cs
@@ -105,7 +105,7 @@ public static bool IPv6(string address)
             {
                 return false; //reject simple IPv6 Zero
             }
-
+            
             //Find and reject other ways of making IPv6 Zero
             Match zeroResult = Regex.Match(address, "^s*(((0{1,4}:){7}(0{1,4}|:))|((0{1,4}:){6}|(:))|((0{1,4}:){5}(((:0]{1,4}){1,2})|:))|((0{1,4}:){4}(((:0{1,4}){1,3})|((:0{1,4})?:)|:))|((0{1,4}:){3}(((:0{1,4}){1,4})|((:0{1,4}){0,2}:)|:))|((0{1,4}:){2}(((:0{1,4}){1,5})|((:0{1,4}){0,3}:)|:))|((0{1,4}:){1}(((:0{1,4}){1,6})|((:0{1,4}){0,4}:)|:))|(:(((:0{1,4}){1,7})|((:0{1,4}){0,5}:)|:)))(%.+)?s*");
             if (zeroResult.Value == address)
@@ -190,15 +190,16 @@ public static bool IPv4CIDR(string address)
                 return false;
             }
 
-            if (!IPv4(SplitCIDR[0]))
+            string AddressVal = SplitCIDR[0];
+            if (!int.TryParse(SplitCIDR[1], out int CIDRVal))
             {
-                //Front part isn't a valid address
+                //Unable to turn second part into int
                 return false;
             }
 
-            if (!int.TryParse(SplitCIDR[1], out int CIDRVal))
+            if (!(AddressVal == "0.0.0.0" || IPv4(AddressVal)))
             {
-                //Unable to turn second part into int
+                //Front part isn't 0.0.0.0 or a valid address
                 return false;
             }
 
@@ -207,7 +208,12 @@ public static bool IPv4CIDR(string address)
                 return false;
             }
 
-            if (CIDRVal <= 0)
+            if (CIDRVal < 0)
+            {
+                return false;
+            }
+
+            if (CIDRVal == 0 && AddressVal != "0.0.0.0")
             {
                 return false;
             }
@@ -461,4 +467,4 @@ public static bool PackageId(string id)
             }
         }
     }
-}
\ No newline at end of file
+}
diff --git a/DPCLibraryTests/ValidateTests.cs b/DPCLibraryTests/ValidateTests.cs
index 076de47..d09f6d9 100644
--- a/DPCLibraryTests/ValidateTests.cs
+++ b/DPCLibraryTests/ValidateTests.cs
@@ -29,9 +29,9 @@ public class ValidateTests
         [DataRow("1.1.1.1/-1")]
         [DataRow("1.1.1.1/33")]
         [DataRow("1.1.1.1/bob")]
-        [DataRow("2001:0db9::1/64")]
-        [DataRow("2001:0db9::1")]
         [DataRow("192.168..1/32")]
+        [DataRow("192.168.1.1/0")]
+        [DataRow("0.0.0.0")]
         public void InvalidIpv4ORCIDR(string IPv4Address)
         {
             bool result = Validate.IPv4OrCIDR(IPv4Address);
@@ -50,6 +50,8 @@ public void InvalidIpv4ORCIDR(string IPv4Address)
         [DataRow("192.168.0.0/16")]
         [DataRow("192.168.1.1/32")]
         [DataRow("20.1.2.3/32")]
+        [DataRow("0.0.0.0/1")]
+        [DataRow("0.0.0.0/0")]
         public void ValidIpv4ORCIDR(string IPv4Address)
         {
             bool result = Validate.IPv4OrCIDR(IPv4Address);
@@ -150,13 +152,7 @@ public void InvalidIpv6CIDR(string IPv6Address)
         [DataRow("255.255.255.255")]
         [DataRow("20.1.2.3")]
         [DataRow("0.0.0.0")]
-        [DataRow("10.0.0.0")]
-        [DataRow("172.16.35.3")]
-        [DataRow("192.168.5.4")]
-        [DataRow("255.255.255.255")]
-        [DataRow("20.1.2.3")]
         [DataRow("172.16.0.0/12")]
-        [DataRow("10.32.99.0/24")]
         [DataRow("192.168.0.0/16")]
         [DataRow("192.168.1.1/32")]
         [DataRow("20.1.2.3/32")]
@@ -203,6 +199,8 @@ public void ValidIpv6ORCIDR(string IPv4Address)
         [DataRow("192.168.0.0/16")]
         [DataRow("192.168.1.1/32")]
         [DataRow("20.1.2.3/32")]
+        [DataRow("0.0.0.0/1")]
+        [DataRow("0.0.0.0/0")]
         public void ValidIpv4ORIpv6ORCIDR(string IPv4Address)
         {
             bool result = Validate.IPv4OrIPv6OrCIDR(IPv4Address);
@@ -424,6 +422,8 @@ public void InvalidIpv4CIDR(string IPv4Address)
         [DataRow("192.168.0.0/16")]
         [DataRow("192.168.1.1/32")]
         [DataRow("20.1.2.3/32")]
+        [DataRow("0.0.0.0/1")]
+        [DataRow("0.0.0.0/0")]
         public void ValidIpv4CIDR(string IPv4Address)
         {
             bool result = Validate.IPv4CIDR(IPv4Address);