diff --git a/orcid-api-common/src/main/java/org/orcid/api/common/exception/JSONInputValidator.java b/orcid-api-common/src/main/java/org/orcid/api/common/exception/JSONInputValidator.java
index deae4c7b415..f47ba410bac 100644
--- a/orcid-api-common/src/main/java/org/orcid/api/common/exception/JSONInputValidator.java
+++ b/orcid-api-common/src/main/java/org/orcid/api/common/exception/JSONInputValidator.java
@@ -12,6 +12,7 @@
 import javax.xml.validation.SchemaFactory;
 import javax.xml.validation.Validator;
 
+import org.apache.commons.lang3.exception.ExceptionUtils;
 import org.orcid.core.exception.ApplicationException;
 import org.orcid.core.exception.InvalidJSONException;
 import org.slf4j.Logger;
@@ -31,7 +32,6 @@ public class JSONInputValidator {
     
     static {
         SCHEMA_LOCATIONS = new HashMap<>();
-
        
         SCHEMA_LOCATIONS.put(org.orcid.jaxb.model.v3.release.record.Work.class, "/record_3.0/work-3.0.xsd");
         SCHEMA_LOCATIONS.put(org.orcid.jaxb.model.v3.release.record.Funding.class, "/record_3.0/funding-3.0.xsd");
@@ -128,15 +128,36 @@ public void validateJSONInput(Object obj) {
         
         try {
             source = new JAXBSource(CONTEXTS.get(clazz), obj);
-            VALIDATORS.get(clazz).validate(source);
+            Validator validator = VALIDATORS.get(clazz);
+            if(validator != null) {
+                validator.validate(source);
+            } else {
+                LOGGER.error("Unable to find validator for class " + clazz.getName());
+                Map<String, String> params = new HashMap<>();
+                params.put("error", "Unable to find validator for class " + clazz.getName());
+                throw new InvalidJSONException(params);
+            }
         } catch (SAXException e) {
             Map<String, String> params = new HashMap<>();
-            params.put("error", e.getCause().getCause().getMessage());
+            Throwable rootCause = ExceptionUtils.getRootCause(e);
+            if(rootCause != null) {
+                params.put("error", rootCause.getMessage());
+            } else {
+                // For SAXException, the message is usually 2 levels deep
+                params.put("error", e.getCause().getCause().getMessage());
+            }
             throw new InvalidJSONException(params);
         } catch (Exception e) {
-            LOGGER.error("General exception from json validator", e);
-            throw new ApplicationException(e);
-        } 
+            LOGGER.error("Unable to find validator for class " + clazz.getName());
+            Map<String, String> params = new HashMap<>();
+            Throwable rootCause = ExceptionUtils.getRootCause(e);
+            if(rootCause != null) {
+                params.put("error", rootCause.getMessage());
+            } else {
+                params.put("error", e.getMessage());
+            }
+            throw new InvalidJSONException(params);
+        }
     }
     
     public void validate2_1APIJSONInput(Object obj) {
diff --git a/orcid-api-common/src/main/java/org/orcid/api/common/jaxb/OrcidExceptionMapper.java b/orcid-api-common/src/main/java/org/orcid/api/common/jaxb/OrcidExceptionMapper.java
index 0c0621161b0..f4477a20730 100644
--- a/orcid-api-common/src/main/java/org/orcid/api/common/jaxb/OrcidExceptionMapper.java
+++ b/orcid-api-common/src/main/java/org/orcid/api/common/jaxb/OrcidExceptionMapper.java
@@ -16,6 +16,7 @@
 import javax.ws.rs.ext.Provider;
 
 import org.apache.commons.lang.StringUtils;
+import org.apache.commons.lang3.exception.ExceptionUtils;
 import org.apache.solr.client.solrj.impl.HttpSolrClient.RemoteSolrException;
 import org.jbibtex.TokenMgrError;
 import org.orcid.api.common.filter.ApiVersionFilter;
@@ -132,8 +133,19 @@ public Response toResponse(Throwable t) {
             logShortError(t, clientId);
         } else if (t instanceof MismatchedPutCodeException) {
             logShortError(t, clientId);
+        } else if (t instanceof WrongSourceException) {
+            logShortError(t, clientId);
+        } else if (t instanceof InvalidDisambiguatedOrgException) {
+            logShortError(t, clientId);
+        } else if (t instanceof OrcidWebhookNotFoundException) {
+            logShortError(t, clientId);
         } else {
-            LOGGER.error("An exception has occured processing request from client " + clientId, t);
+            Throwable rootCause = ExceptionUtils.getRootCause(t);
+            if(rootCause != null) {
+                LOGGER.error("An exception has occurred processing request from client " + clientId, rootCause);
+            } else {
+                LOGGER.error("An exception has occurred processing request from client " + clientId, t);
+            }
         }
 
         if (isOAuthTokenRequest()) {
diff --git a/orcid-api-common/src/main/java/org/orcid/api/common/jaxb/OrcidJacksonJaxbJsonProvider.java b/orcid-api-common/src/main/java/org/orcid/api/common/jaxb/OrcidJacksonJaxbJsonProvider.java
index 9287e7b3bb8..64aec889103 100644
--- a/orcid-api-common/src/main/java/org/orcid/api/common/jaxb/OrcidJacksonJaxbJsonProvider.java
+++ b/orcid-api-common/src/main/java/org/orcid/api/common/jaxb/OrcidJacksonJaxbJsonProvider.java
@@ -70,6 +70,11 @@ public Object readFrom(Class<Object> arg0, Type arg1, Annotation[] arg2, MediaTy
             params.put("error", e.getMessage());
             throw new InvalidJSONException(params);
         }
+        if(o == null) {
+            Map<String, String> params = new HashMap<>();
+            params.put("error", "Couldn't read object, data seems to be empty or invalid");
+            throw new InvalidJSONException(params);
+        }
         if (jsonInputValidator.canValidate(o.getClass())) {
             RequestAttributes requestAttributes = RequestContextHolder.getRequestAttributes();
             String apiVersion = (String) requestAttributes.getAttribute(ApiVersionFilter.API_VERSION_REQUEST_ATTRIBUTE_NAME, RequestAttributes.SCOPE_REQUEST);
diff --git a/orcid-core/src/main/java/org/orcid/core/manager/read_only/impl/RecordManagerReadOnlyImpl.java b/orcid-core/src/main/java/org/orcid/core/manager/read_only/impl/RecordManagerReadOnlyImpl.java
index d797f3f5fb0..cad178049c5 100644
--- a/orcid-core/src/main/java/org/orcid/core/manager/read_only/impl/RecordManagerReadOnlyImpl.java
+++ b/orcid-core/src/main/java/org/orcid/core/manager/read_only/impl/RecordManagerReadOnlyImpl.java
@@ -117,7 +117,7 @@ private Preferences getPreferences(String orcid) {
             }
             return preferences;
         } catch(Exception e) {
-            LOGGER.error("Exception loading preferences for " + orcid, e);
+            LOGGER.info("Locale for user " + orcid + " is not valid for V2.0/V2.1 API");
         }
         return null;
     }
diff --git a/orcid-core/src/main/java/org/orcid/core/oauth/service/OrcidOauth2TokenDetailServiceImpl.java b/orcid-core/src/main/java/org/orcid/core/oauth/service/OrcidOauth2TokenDetailServiceImpl.java
index ab98087e127..5b1cbc6c4cb 100644
--- a/orcid-core/src/main/java/org/orcid/core/oauth/service/OrcidOauth2TokenDetailServiceImpl.java
+++ b/orcid-core/src/main/java/org/orcid/core/oauth/service/OrcidOauth2TokenDetailServiceImpl.java
@@ -8,6 +8,7 @@
 import javax.annotation.Resource;
 import javax.persistence.NoResultException;
 
+import org.apache.commons.lang3.StringUtils;
 import org.orcid.core.constants.RevokeReason;
 import org.orcid.core.oauth.OrcidOauth2TokenDetailService;
 import org.orcid.core.utils.cache.redis.RedisClient;
@@ -50,6 +51,9 @@ public void setOrcidOauth2TokenDetailDao(OrcidOauth2TokenDetailDao orcidOauth2To
     
     @Override
     public OrcidOauth2TokenDetail findNonDisabledByTokenValue(String token) {
+        if(StringUtils.isBlank(token)) {
+            return null;
+        }
         try {
             return orcidOauth2TokenDetailDaoReadOnly.findNonDisabledByTokenValue(token);
         } catch (NoResultException e) {