Other [FIXED] Error while verifying Sign Key


Well-Known Member
Licensed User
I am asking the community because I was unable to find the answer using a search engine.

I had to change my computer and reinstalled the necessary tools. I had the copy of my Sign Key (generated in 2013) but was unable to use it because of an error while associating with B4A.
So I have generated a new sign key with B4A yesterday. Today, I have got the same error.

Below is a screenshot and attached a fake sign key with password "testing" if someone would like to test it.

Please, is this on my part ? How could I fix that ? Thanks

java version "1.8.0_152"
Java(TM) SE Runtime Environment (build 1.8.0_152-b16)
Java HotSpot(TM) 64-Bit Server VM (build 25.152-b16, mixed mode)
Error: Type de fichier de clés : JKS
Fournisseur de fichier de clés : SUN
Votre fichier de clés d'accès contient 1 entrée
Nom d'alias : b4a
Date de création : 6 nov. 2017
Type d'entrée : PrivateKeyEntry
Longueur de chaîne du certificat : 1
erreur keytool : java.util.IllegalFormatConversionException: d != java.lang.String
java.util.IllegalFormatConversionException: d != java.lang.String
at java.util.Formatter$FormatSpecifier.failConversion(Formatter.java:4302)
at java.util.Formatter$FormatSpecifier.printInteger(Formatter.java:2793)
at java.util.Formatter$FormatSpecifier.print(Formatter.java:2747)
at java.util.Formatter.format(Formatter.java:2520)
at java.util.Formatter.format(Formatter.java:2455)
at java.lang.String.format(String.java:2940)
at sun.security.tools.keytool.Main.withWeak(Main.java:3076)
at sun.security.tools.keytool.Main.printX509Cert(Main.java:3125)
at sun.security.tools.keytool.Main.doPrintEntry(Main.java:1924)
at sun.security.tools.keytool.Main.doPrintEntries(Main.java:2236)
at sun.security.tools.keytool.Main.doCommands(Main.java:1123)
at sun.security.tools.keytool.Main.run(Main.java:366)
at sun.security.tools.keytool.Main.main(Main.java:359)


  • fake_key.zip
    1.9 KB · Views: 226


Well-Known Member
Licensed User
What happens if you try to compile with this key?
When I try to compile I get an error at the end of the compilation window:

Signing package file (private key). Error
jarsigner error: java.security.InvalidKeyException: The security strength of SHA-1 digest algorithm is not sufficient for this key size

and that, even with my old key
Upvote 0


Licensed User
Hi Erel, i'm new member of this forum, i've the same problem, i can't release with obfuscated my app.
I have jdk 1.8.0_161 and my error is:
B4A Versione: 7.80
Analisi del Codice. (0.02s)
Compilazione del codice. (0.15s)

File ObsucastorMap.txt creato nella cartella Objects.
Compilazione del codice di layouts (0.04s)
Organizzazione Librerie. (0.00s)
Generazione file R. (0.50s)
Compilazione del codice Java prodotto. (2.15s)
Conversione byte code - ottimizzazione dex. (0.78s)
Packaging files. (1.18s)
Copia risorse delle librerie (0.00s)
Firmo il package file ( chiave privata ). Error
jarsigner error: java.security.InvalidKeyException: The security strength of SHA-1 digest algorithm is not sufficient for this key size

p.s. Sorry for my english.

Thank you
Upvote 0