No matter which forum website at home or abroad, it is no longer able to provide certificate creation service for users under the current situation.
The current solution:
1. For software with lower permission requirements, you can try to use the Symbian Direct Signature Tool Mobile v1.21 signature, but there is no guarantee that it will be effective, only that you can try.
2. Of course, you can also crack the phone, the phone cracked after the installation of any software does not require a certificate signature.
But there is a program in the cracking process that needs to be signed, so you may need to sign it with the direct signature tool above.
★If Symbian is reopened by then, you just need to give me the link to this question, and I'll help you make it for free.