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i stummbled across an old post regarding this topic. however it was never really answered. and i am fairly new to the plc world. so if anyone can explain in great detail how to remove the KNOW_HOW_PROTECT from a s7 block. that would be great.

thanks alot

to reset know-how-protect of a SIEMENS S7-Function Block just follow this little recipe:

Open the following file in your S7 project's main folder with a hex editor (yon can get many good and free hex editor tools by using google, for example with *HEX-Wizard* or *Winhex*):nameofyourproject\ombstx\offline\00000001\SUBBLK.DBF

With your hex-editor search for ASCII-String, e.g. "1400100" for function block number FB100 (140=FB, 120=FC, 0100= Number of function block). That means, search for ascii-string "1400059" if you would like to unprotect the funtion FB59

To the found address you just add 84 decimal (or 54hex) and go to the line of this calculated new adress and look for a hex-number "33" in this line. (there must be a 33, if everything went right until here)

Simple replace this "33" by "30"

Save your file an re-open step 7.

6) The know-how-protect should be reset.

I've successfully used this described process above, but sometimes had to close and re-open step7 more than one or two times - for whatever reason! There are also some tools (e.g. "s7canopener") on the internet which may also unprotect protected functions in a more easy OR more comfortable way, but I never really get them running.

If you have any further questions- you know: this is a good place to ask them!
Good luck
and greetings from Germany,

Hello Marco!

I would like to know, if it procedure can also be used unlook ST blook creation in Simotion Scout by Siemens.

Thank very much for you attention.
> to reset know-how-protect of a SIEMENS S7-Function Block just follow this little recipe: <

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Thx Works but i don't know how to do in a multi project, i don't find any 0000000001 directory