hallo , meine festplatte hat sich verabschiedet, hab nun einen neuen pc und wollte lightroom neu herunterladen und mit meiner serialnummer aktivieren..., leider wird meine nummer nicht mehr erkannt was kann ich machen ? danke für ne Antwort

you need your serial number.  if you have that download the installation file(s) and install,

Downloadable installation files available:

• Suites and Programs:  CC 2014 | CC | CS6 | CS5.5 | CS5 | CS4 | CS3
• Acrobat:  XI, X | 9,8 | 9 standard
• Premiere Elements:  13 | 12 | 11, 10 | 9, 8, 7 win | 8 mac | 7 mac
• Photoshop Elements:  13 |12 | 11, 10 | 9,8,7 win | 8 mac | 7 mac
• Lightroom:  5.7.1| 5 | 4 | 3
• Captivate:  8 | 7 | 6 | 5.5, 5
• Contribute:  CS5 | CS4, CS3

Download and installation help for Adobe links

Download and installation help for Prodesigntools links are listed on most linked pages.  They are critical; especially steps 1, 2 and 3.  If you click a link that does not have those steps listed, open a second window using the Lightroom 3 link to see those 'Important Instructions'.