Home » Technical » PLC & HMI » SIEMENS » SIEMENS PLC S7 Can Opener Full Version

SIEMENS PLC S7 Can Opener Full Version

wpb6974ac0_06S7 Can Opener

Set and remove the lock on the KNOW HOW PROTECT on S7-300/400 blocks!

NOTE: it does NOT unlock latest S7  v5.5 “Block privacy” protection

Steps to Unlock the Blocks









Language supported: English only.

Download S7CanOpener manual

Current version is v2.0
If you are a registered user and own an older release, contact us for a free update.

 S7CanOpener FAQs

Q: What’s the S7CanOpener purpose?

A: the S7CanOpener can unlock S7 blocks protected with the “know_how_protect” keyword.

Q: Can it unlock also S7 libraries?

A: Yes, it works on S7programs (*.s7p) and S7libraries (*.s7l)

Q: Can it unlock Step7 v5.5 new “Block Privacy” protection ?

A: No, at the moment the tool is not able to decrypt such protection.

Q: I have a PLC that requires a password for online operations, can I use the S7CanOpener to defeat the password?

A: No. The S7CanOpener operates on projects stored on the hard disk, it does not operate online in the PLC memory and does not remove the password set in the CPU at hardware configuration level.

Q: Will I be able to read the comments within an unlocked block?

A: Yes, if the original block contained comments.

Q: I have some SCL or CFC blocks, can I reverse the code to obtain the source file?

A: No. In case you have SCL, CFC, GRAPH7, HIGRAPH blocks, once unlocking them you will get the compiled version of the block or, in other words, plain STL code with no comments and no variables name at all.  If you expected the full-source text file, it is not possible: in that case your only chance is to get the original SCL or CFC source file.  On the other hand, if you are however interested in the blocks’ contents, you have a way to peep into the STL version of the code.

Q: Can I lock/unlock UDTs?

A: Yes, from version v1.4 you can lock also UDT (User Data Type) blocks. Unlike all other blocks (OB, FC,FB), a protected UDT cannot be modified but its contents can be displayed.

Q: Can I unlock SFCs and SFBs?

A: SFCs and SFBs cannot be unlocked since they are functions stored in the PLC’s system memory and cannot be read. What we see and use in S7 is just the block’s interface (parameters assignment) and not the complete block.  Offline SFCs and SFBs contain no S7


Demo Version S7 Can Opener v1.3


S7 Can Opener Full Version


About engrsajidrehman

I am an Electronics Engineer by profession and currently is a Service Engineer in European Based Textile Machinery Manufacturing Company. Beside all this I'm a Web Designer, Graphics Designer, Content writer. I love to explore places and new things. You can contact him on Google, Linkedin, and subscribe my YouTube Channel for cool stuff Thanks

Check Also

EKB Install 2018 TIA 15

Simatic EKB Install 2018 TIA Portal 15 Full Download

Simatic EKB Install 2018| 3041 keys v2018.08.19 add info for Sinumeric v4.8, Sinamics StartDrive v15 8b18c85790ed809c7ca863fada244cfd ...