3390730 - "PSE does not exist or File not found!" in SAP Web Dispatcher trace

When trying to access a URL through Sap Web dispatcher the "503 Service not available" or "503 Service Unavailable" error is reported.

When checking the Web Dispatcher traces, the following can be observed:

[Thr 7432] =   current UserID:<user id>
[Thr 7432] =   found SECUDIR environment variable
[Thr 7432] =   using SECUDIR=<path to pse>
[Thr 7432] = [ipf] ssl/server_pse=<pse file name>
[Thr 7432] =       resulting Filename = "<pse file name>"
[Thr 7432] = [ipf] ssl/client_pse=<pse file name>
[Thr 7432] =       resulting Filename = "<pse file name>"
[Thr 7432] =   automagic TLS extension SNI enabled
[Thr 7432] = [ctc] ssl/ciphersuites=135:PFS:HIGH::EC_P256:EC_HIGH
[Thr 7432] = [ctc] ssl/client_ciphersuites=150:PFS:HIGH::EC_P256:EC_HIGH
[Thr 7432] *** ERROR =>   secussl_Create_SSL_CTX():  PSE ",path to pse>": PSE does not exist or File not found! [ssslsecu.c   3317]
[Thr 7432] secussl_Create_SSL_CTX: SSL_CTX_set_default_pse_by_name() failed  (4129/0x00001021)
[Thr 7432]    => "The PSE file does not exist."
[Thr 7432] >> ===== SecuSSL ErrStack: =====
[Thr 7432] The PSE file does not exist.
[Thr 7432] 0xa1d50108 | TOKEN_TOKPSE | SSL_CTX_set_default_pse_by_name
[Thr 7432] Token application not existing
[Thr 7432] Cannot open PSE (PSE=<path to pse>, SECUDIR=<path to pse>, user=<adm user>)
[Thr 7432] 0xa1d50108 | TOKEN_TOKPSE | sec_SSL_CTX_set_asc
[Thr 7432] Token application not existing
[Thr 7432] << =============================
[Thr 7432] *** ERROR => SapISSLAddCredential(): Error SSSLERR_PSE_NOT_EXISTING trying to create SERVER Credential
        for "<path to pse>" [ssslxxi.c    3669]
[Thr 7432] *** ERROR => Initialization of SSL library failed -- NO SSL available!

SAP Web Dispatcher

PSE, not, exist, sap, web dispatcher, PSE does not exist or File not found!, SSSLERR_PSE_NOT_EXISTING, SAPSSLS.pse, ssl/server_pse,  ssl/client_pse, SSL_CTX_set_default_pse_by_name() failed , KBA , BC-CST-WDP , Web Dispatcher , Problem