diff --git a/libraries/databaseTools.py b/libraries/databaseTools.py
index 267550984..d275b6992 100644
--- a/libraries/databaseTools.py
+++ b/libraries/databaseTools.py
@@ -1045,7 +1045,7 @@ class etpDatabase:
         # sources, a list
         for source in etpData['sources']:
 
-            if (not source) or (source == "") or (not source.isalnum()):
+            if (not source) or (source == "") or (not entropyTools.is_valid_string(source)):
                 continue
 
             idsource = self.isSourceAvailable(source)
@@ -1362,7 +1362,7 @@ class etpDatabase:
         raise exceptionTools.CorruptionError("CorruptionError: I tried to insert a needed library but then, fetching it returned -1. There's something broken.")
 
     def addLicense(self,pkglicense):
-        if not pkglicense.isalnum():
+        if not entropyTools.is_valid_string(pkglicense):
             pkglicense = ' ' # workaround for broken license entries
         self.cursor.execute(
                 'INSERT into licenses VALUES '
@@ -2499,7 +2499,7 @@ class etpDatabase:
         licdata = {}
         for licname in licenses:
             licname = licname.strip()
-            if not licname.isalnum():
+            if not entropyTools.is_valid_string(licname):
                 continue
             self.cursor.execute('SELECT text FROM licensedata WHERE licensename = (?)', (licname,))
             lictext = self.cursor.fetchone()
@@ -2527,7 +2527,7 @@ class etpDatabase:
         licdata = set()
         for licname in licenses:
             licname = licname.strip()
-            if not licname.isalnum():
+            if not entropyTools.is_valid_string(licname):
                 continue
             self.cursor.execute('SELECT licensename FROM licensedata WHERE licensename = (?)', (licname,))
             licidentifier = self.cursor.fetchone()
@@ -2747,7 +2747,7 @@ class etpDatabase:
         self.commitChanges()
 
     def isLicenseAvailable(self,pkglicense):
-        if not pkglicense.isalnum():
+        if not entropyTools.is_valid_string(pkglicense):
             pkglicense = ' '
         self.cursor.execute('SELECT idlicense FROM licenses WHERE license = (?)', (pkglicense,))
         result = self.cursor.fetchone()
@@ -2832,7 +2832,7 @@ class etpDatabase:
 
     def searchLicenses(self, mylicense, caseSensitive = False, atoms = False):
 
-        if not mylicense.isalnum():
+        if not entropyTools.is_valid_string(mylicense):
             return []
 
         request = "baseinfo.idpackage"
@@ -3885,8 +3885,6 @@ class etpDatabase:
             mylicenses = mylicenses.strip().split()
             if mylicenses:
                 for mylicense in mylicenses:
-                    if not mylicense.isalnum():
-                        continue
                     if mylicense in etpConst['packagemasking']['license_mask']:
                         idpackageValidatorCache[(idpackage,reponame)] = -1,10
                         return -1,10
diff --git a/libraries/entropyTools.py b/libraries/entropyTools.py
index a458d6b92..926d9e020 100644
--- a/libraries/entropyTools.py
+++ b/libraries/entropyTools.py
@@ -2111,8 +2111,9 @@ def extractPkgData(package, etpBranch = etpConst['branch'], silent = False, inje
         pass
     data['licensedata'] = {}
     if licenses_dir:
-        licdata = [x.strip() for x in data['license'].split() if x.strip().isalnum()]
+        licdata = [str(x.strip()) for x in data['license'].split() if str(x.strip()) and is_valid_string(x.strip())]
         for mylicense in licdata:
+
             licfile = os.path.join(licenses_dir,mylicense)
             if os.access(licfile,os.R_OK):
                 if istextfile(licfile):
@@ -2196,6 +2197,13 @@ def extractPkgData(package, etpBranch = etpConst['branch'], silent = False, inje
     if not silent: print_info(yellow(" * ")+red(info_package+"Done"),back = True)
     return data
 
+def is_valid_string(string):
+    mystring = str(string)
+    for char in mystring:
+        if ord(char) not in range(32,127):
+            return False
+    return True
+
 def collectLinkerPaths():
     if linkerPaths:
         return linkerPaths