cannot open php file

Question

i have downloaded some php files (it's a content management system) but i can't open them. it appears that they contain binary data. this is what i get when i open them using a text editor:

Zend20020623011793334417xù ں2ف=كڈإ™m{Orvƒًè¢9 ­ف]UفU0زع^ہ€eo.’ذî™éفïىجhzcë‌ن7,‏xAœگrBBو$89¯‘<"‌ٍs~±B¤كغتز‎Zء¤ص€1c‍Xû‡ûû×O¦أل¼\آ=o…ر¨ّzـ;^´>®é3ُéJہإً_±w[ƒٍµh‍يŒٍE6Ovئس~:.$َügLk,{+»9*گ~m.إ5طû¤ْW%&&aد؛fجMe´?›خة<ƒط<_$o¦َ—Q^4ûJ§{ç/‍صg}u¥kڈnFق0غM2‏#5شl\‏ظو›—.©3 ق?h+<Wٍ9LkئPïھة¤4ےbإ9…ھ â8”8'´‘گwٍشQf~[أي­Bى}VC‘ هNç،Œح]ڈق~[ƒ‰ف:ô¾6Wںنüو–¤‍£ôُe½ئـة÷g%ت»®-­ىلƒپآڈUˆ%©يئ‘B~نKٍ©,ةgڑCLاcپء¼اثYiآ9†ںئأ,?5طفمjک'g»³²ص_Jں&÷èQM+ƒZS=c¾03¥–xwجMB~­TN±‹`قƒ²

(there is much more, about 50 lines)
what is this? i have never worked with Zend, is it some kind of compression? how can i open and edit these files?

Answer 1

This file appears to be encoded by Zend guard. You probably cannot decode it. Here is something you can read on http://www.zend.com/en/products/guard/

Answer 2

Encoded PHP file. Protecting their source code