[BitBucket user: Sébastien Jodogne]
[BitBucket date: 2017-07-05.14:14:48]

Hello,

I am not able to reproduce your issue. Starting with our [DummyCT.dcm](https://hg.orthanc-server.com/orthanc-tests/file/default/Database/DummyCT.dcm) sample image, let's create another series with the same name, and store it into Orthanc:

```
$ cp DummyCT.dcm DummyCT2.dcm
$ dcmodify --gen-inst-uid --gen-ser-uid ./DummyCT2.dcm
$ storescu localhost 4242 ./DummyCT.dcm DummyCT2.dcm
```

This results in one study, containing 2 series sharing almost all the same DICOM tags (they notably have the same name, i.e. the same "SeriesDescription"):

```
$ curl http://localhost:8042/series?expand
[
   {
      "ID" : "f2635388-f01d497a-15f7c06b-ad7dba06-c4c599fe",
      "Instances" : [ "66a662ce-7430e543-bad44d47-0dc5a943-ec7a538d" ],
      "LastUpdate" : "20170705T160359",
      "MainDicomTags" : {
         "SeriesDate" : "20070101",
         "SeriesDescription" : "AX.  FSE PD",
         "SeriesInstanceUID" : "1.2.840.113619.2.176.2025.1499492.7391.1171285944.394"
      },
      "ParentStudy" : "b9c08539-26f93bde-c81ab0d7-bffaf2cb-a4d0bdd0",
      "Type" : "Series"
   },
   {
      "ID" : "b51d89ab-b4db9f8f-66f823d4-6cc53b67-77cbce82",
      "Instances" : [ "ab8512cc-554f19c8-0227b576-ef28dd7e-49247d77" ],
      "LastUpdate" : "20170705T160359",
      "MainDicomTags" : {
         "SeriesDate" : "20070101",
         "SeriesDescription" : "AX.  FSE PD",
         "SeriesInstanceUID" : "1.2.276.0.7230010.3.1.3.8323329.2669.1499263439.858655"
      },
      "ParentStudy" : "b9c08539-26f93bde-c81ab0d7-bffaf2cb-a4d0bdd0",
      "Type" : "Series"
   }
]
```

Now, let's download and unzip the corresponding archive:

```
$ curl http://localhost:8042/studies/b9c08539-26f93bde-c81ab0d7-bffaf2cb-a4d0bdd0/archive > a.zip
$ unzip a.zip 
Archive:  a.zip
Created by Orthanc
  inflating: ozp00SjY2xG KNIX/Knee R/MR AX. FSE PD/MR000000.dcm  
  inflating: ozp00SjY2xG KNIX/Knee R/MR AX. FSE PD-2/MR000000.dcm  
```

As can been seen, there are 2 distinct folders, and nothing was overwritten.

Please provide sample files to reproduce this issue. In the meantime, I put this issue on hold.