Package installation is the only way to upgrade to 6.5.19Follow below link, similarly we can upgrade. First perform dry run in local before running on dev or any other environments.https://experienceleaguecommunities.adobe.com/t5/adobe-experience-manager/instructions-needed-for-setting-up-local-aem-...

Follow below for the samehttp://www.sgaemsolutions.com/2019/01/dynamically-populate-drop-down-values.html

@Uppari_Ramesh  PROS and CONS for servlet by path and resource typehttps://sourcedcode.com/blog/aem/aem-sling-servlet-resource-type-for-post-get-code-example-codeImplementationhttps://medium.com/@toimrank/aem-sling-servlet-ca9e5926a384#:~:text=Using%20Paths,use%20to%20register%20a%20servlet.Write ap...

@Uppari_Ramesh cool, Congratulations !!!

We can't access system console directly in AEMaaCS. If it's for any OSGI configuration it has to be deployed via code. For more detailshttps://experienceleaguecommunities.adobe.com/t5/adobe-experience-manager/how-can-i-access-aem-as-cloud-service-system-console-for-both/m-p/419949 for crx/de please ...

@Prince_Shivhare We can take backup of users, groups and ACL's of DEV instance. After reset we can reinstall package.Before performing all above steps please perform a dry run in local to verify users, groups and its ACL's.

@stiegjo22 Follow below article to read the asset in correct way will resolve your issue:https://experienceleaguecommunities.adobe.com/t5/adobe-experience-manager/attach-pdf-with-email/m-p/238864

@chandanaa9 I was also having this issue last week and got resolved after setting below configurations DispatcherUseProcessedURL OnDispatcherPassError 1 Follow below link for more detailshttps://experienceleaguecommunities.adobe.com/t5/adobe-experience-manager/aem-dispatcher-errordocument-url-not-sh...

@Vani1012 Component doesn't depend on templates. Yes, we can use same component in both static and editable template. The only prerequisite is to have that component specific clientlib loading as part of both the templates.

@Uppari_Ramesh please verify ip/domain whitelisting within client and server you are trying to connect. Also, try to disable proxy server settings or VPN Connections. Turn Off the firewall and antivirus software temporarily.