TFS Integration Tools: Version Control to Version Control - nothing really happens

I've just investigated TFS Integration Tools to migrate all source code along with the history from one TFS server 2010 to another, and I have experienced a strange behaviour. Here are my actions:

1. Installed TFS Server locally.
2. Created two project collections and project in each of them (Source project and Target project).
3. Filled Source project with some files, made several check-outs and check-ins.
4. Launched TFS Integration Tools.
5. Created new configuration with template VersionControl.xml
6. Chosen Source project as a Left Source and Target project as a Right Source.
7. Started the migration. Everything was well, I could see all history in the progress window.

And the result of these actions is the following - nothing changed. Literally. I expected that the source control of the Target project will be filled with files from Source project's ones. But both projects remained exactly as they were.

What am I missing? What have I misunderstood about the TFS Integration Tools?

Update

Here is the config that was generated by the application:

<?xml version="1.0" encoding="utf-16"?>
<Configuration xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w开发者_JS百科3.org/2001/XMLSchema" UniqueId="cdf29df8-c74f-4339-b96f-7eb621c1cee1" FriendlyName="TFS to TFS Version Control">
  <Providers>
    <Provider ReferenceName="febc091f-82a2-449e-aed8-133e5896c47a" FriendlyName="TFS 2010 Migration VC Provider" />
  </Providers>
  <Addins />
  <SessionGroup CreationTime="2011-04-28T11:24:10.9503239Z" FriendlyName="TFS to TFS Version Control" SessionGroupGUID="394da96f-b8b6-4bc1-9b72-1c6234c4b9f1" Creator="<domain>\<user_name>" SyncIntervalInSeconds="0" SyncDurationInMinutes="0">
    <MigrationSources>
      <MigrationSource InternalUniqueId="181ddf3d-9cdb-461a-9dba-4338cf2a02f8" FriendlyName="<server_name> (VC)" ServerIdentifier="c0a0f4e4-4a37-4a89-ba23-fbd323680786" ServerUrl="http://<server_name>:8080/tfs/sourcecollection" SourceIdentifier="SourceProject" ProviderReferenceName="febc091f-82a2-449e-aed8-133e5896c47a" EndpointSystemName="TFS">
        <Settings>
          <Addins />
          <UserIdentityLookup />
          <DefaultUserIdProperty UserIdPropertyName="DisplayName" />
        </Settings>
        <CustomSettings />
        <StoredCredential />
      </MigrationSource>
      <MigrationSource InternalUniqueId="e292262f-9479-490f-b5e3-ce7e845d1468" FriendlyName="<server_name> (VC)" ServerIdentifier="f01ebcec-ea18-4933-b3fd-751740904136" ServerUrl="http://<server_name>:8080/tfs/targetcollection" SourceIdentifier="Target" ProviderReferenceName="febc091f-82a2-449e-aed8-133e5896c47a" EndpointSystemName="TFS">
        <Settings>
          <Addins />
          <UserIdentityLookup />
          <DefaultUserIdProperty UserIdPropertyName="DisplayName" />
        </Settings>
        <CustomSettings />
        <StoredCredential />
      </MigrationSource>
    </MigrationSources>
    <Sessions>
      <Session CreationTime="2011-04-28T11:24:10.9333256Z" SessionUniqueId="4aa097f3-9a01-4924-b562-384215b4ef2f" FriendlyName="Version Control Session" LeftMigrationSourceUniqueId="181ddf3d-9cdb-461a-9dba-4338cf2a02f8" RightMigrationSourceUniqueId="e292262f-9479-490f-b5e3-ce7e845d1468" SessionType="VersionControl">
        <EventSinks />
        <CustomSettings>
          <SettingXml />
          <SettingXmlSchema />
        </CustomSettings>
        <Filters>
          <FilterPair Neglect="false">
            <FilterItem MigrationSourceUniqueId="181ddf3d-9cdb-461a-9dba-4338cf2a02f8" FilterString="$/SourceProject" />
            <FilterItem MigrationSourceUniqueId="e292262f-9479-490f-b5e3-ce7e845d1468" FilterString="$/Target" />
          </FilterPair>
        </Filters>
      </Session>
    </Sessions>
    <Linking>
      <CustomSettings />
      <LinkTypeMappings />
    </Linking>
    <WorkFlowType Frequency="ContinuousManual" DirectionOfFlow="Unidirectional" SyncContext="Disabled" />
    <CustomSettings />
    <UserIdentityMappings EnableValidation="false">
      <UserIdentityLookupAddins />
    </UserIdentityMappings>
    <ErrorManagement>
      <ErrorRouters />
      <ReportingSettings />
    </ErrorManagement>
  </SessionGroup>
</Configuration>

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Only thing that looks out is that the value ServerIdentifier attribute on the two MigrationSource's is different, as this is a single server deployment they should be the same, can't think of a reason it should matter though - but it is the only thing that I would change.

Everything else in your config is fine.

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I must admit that this is really strange, but the issue is solved. I haven't done any changes to configuration, but when I've reran the migration everything worked - all source code appeared in Target project source control along with check-ins history. Moreover, I've created another empty Target project and migration worked fine as well. It seems that the problem was caused by some temporary TFS Integration Tools fluctuation.