diff --git a/src/com/company/Version.java b/src/com/company/Version.java
index a5d45c5..19368e5 100644
--- a/src/com/company/Version.java
+++ b/src/com/company/Version.java
@@ -26,7 +26,7 @@ public enum Version {
         Matcher m ;
 
         if (!pattern_stable_release.matcher(min).find() || !pattern_stable_release.matcher(last).find()) {
-            throw new Error("VersionCheck: wrong format for min or last version given");
+            throw new IllegalArgumentException("VersionCheck: wrong format for min or last version given");
         }
 
         m = pattern_stable_release.matcher(value);
@@ -74,7 +74,7 @@ public enum Version {
 
         switch (range_check) {
             case 2:
-                throw new Error("Minimum Version higher than Last Version");
+                throw new IllegalArgumentException("Minimum Version higher than Last Version");
             case 1: //min == last
                 switch (min_check) {
                     case 0:
@@ -101,6 +101,9 @@ public enum Version {
      * 2 = more
      */
     public static int compare(String A, String B) {
+        //throw new IllegalArgumentException
+        if((!A.matches("[0-9]+(\\.[0-9]+)*")) || (!B.matches("[0-9]+(\\.[0-9]+)*"))) throw new IllegalArgumentException("Invalid version format");
+
         if (A.contains(".") || B.contains(".")) {
             // example 2 vs 1.3
             if (!(A.contains(".") && B.contains("."))) {