I'm trying to redownload my Lightroom 5 from a disc that i purchased but it said error 1335. I was wondering if I have proof of purchase if I can try downloading it from the adobe site.

Error 1335 is an installation media source error .

You may download LR 5 from below link and try to install :

Install Photoshop Lightroom

You may download anything you want... you may only install with a serial number

Download & Install instructions https://forums.adobe.com/thread/2003339 may help

-includes a way to go to a page to download Adobe programs if you don't have a disc or drive

-Cloud desktop http://helpx.adobe.com/creative-cloud/help/creative-cloud-desktop.html

-Cloud Getting Started https://helpx.adobe.com/creative-cloud.html

-you will need to enter your original serial number during install for non-Cloud programs

-or kglad links in reply #1 here https://forums.adobe.com/thread/2081216 may help

Also go to https://forums.adobe.com/community/creative_cloud/creative_cloud_faq

Downloadable installation files available:

• Suites and Programs:  CC 2015 | CC 2014 | CC | CS6 | CS5.5 | CS5 | CS4, CS4 Web Standard | CS3
• Acrobat:  DC, XI, X | X Suite | 9,8 | 9 standard    | 8 standard
• Captivate:  9 | 8 | 7 | 6 | 5.5, 5 | 1
• Cold Fusion:  11, 10 | 9.0.2, 9.0.1, 9.0.0, 8.0.1, 8.0.0, 7.0, 6.1, 6.0, 5.0, 4.0
• Contribute:  CS5 | CS4, CS3 | 3,2
• FrameMaker:  12, 11, 10, 9, 8, 7.2
• Lightroom:  6.4|  6| 5.7.1| 5 | 4 | 3
• Photoshop Elements:  14,13,12,11,10 | 9,8,7 win | 8 mac | 7 mac
• Premiere Elements:  14,13,12,11,10| 9, 8, 7 win | 8 mac | 7 mac

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'.