This is a known issue documented within the Microfocus knowledge base under article KM02863020.
When the ''Microsoft Root Certificate Program'' is disabled, this can cause the root CA not to be downloaded/updated automatically.
If the root CA is not installed, when downloading ALM client on a client machine, we will see the error you are experiencing.
In ALM 12.55, was introduced a new timestamping CA - GlobalSign. To have the ALM client downloaded and installed correctly, we need the client machines to have the root certificate of GlobalSign installed.
In addition, Verisign is also used for some files. It should also be installed if the client machine doesn't have it already installed.
Download and import the certificate from https://support.globalsign.com/customer/portal/articles/1426602-globalsign-root-certificates using certmgr MMC. You might want to download the ''Global Sign Root R1'' certificate.
Download and import the certificate from https://knowledge.symantec.com/support/ssl-certificates-support/index?page=content&actp=CROSSLINK&id=INFO4159#lightbox-06 using certmgr MMC. You might want to download the ''Microsoft Authenticode....''
This should correct the issue that you are experiencing.