Issues with Views

I am having mega issues with the views after upgrading.

I cannot appear to create a view which has the criteria of the 'Current Month' or per 'User' - returned with the following error code.

Unhandled Exception: System.ServiceModel.FaultException`1[[Microsoft.Xrm.Sdk.OrganizationServiceFault, Microsoft.Xrm.Sdk, Version=5.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35]]: System.Xml.XmlException: Microsoft Dynamics CRM has experienced an error. Reference number for administrators or support: #6A6DA56CDetail:

<OrganizationServiceFault xmlns:i="www.w3.org/.../XMLSchema-instance" xmlns="schemas.microsoft.com/.../Contracts">

 <ErrorCode>-2147220970</ErrorCode>

 <ErrorDetails xmlns:d2p1="schemas.datacontract.org/.../System.Collections.Generic" />

 <Message>System.Xml.XmlException: Microsoft Dynamics CRM has experienced an error. Reference number for administrators or support: #6A6DA56C</Message>

 <Timestamp>2013-08-05T15:56:00.4735272Z</Timestamp>

 <InnerFault>

   <ErrorCode>-2147217104</ErrorCode>

   <ErrorDetails xmlns:d3p1="schemas.datacontract.org/.../System.Collections.Generic" />

   <Message>Table alias a_34e7bb29d7d04dcb985d78a992c283cc is not unique amongst all top-level table and join aliases</Message>

   <Timestamp>2013-08-05T15:56:00.4735272Z</Timestamp>

   <InnerFault i:nil="true" />

   <TraceText i:nil="true" />

 </InnerFault>

 <TraceText i:nil="true" />

</OrganizationServiceFault>

I have also found that I can edit existing views, but not create new ones with this criteria.

Any help would be greatly appreciated.

Thanks,

Sarah