Vikrant -
I noticed you said that on the same machine 7.10 works. I assume originally you had 7.10 and then removed it and installed 7.30. Are you removing 7.30 and re-installing 7.10? If so, please try this.
I have run into issues similar and it was because there were files and items still remaining from a previous install. The uninstalling was leaving many entries behind in the registry and on the machine. (sometimes up to 100+ in the registry) To work around this, I would install a free utility called CCleaner. (https://www.piriform.com/ccleaner)
Once you have removed the SAP GUI from Add/Remove programs, navigate to C:\Program Files or (Program Files x86) and delete the SAP folder. Then I would run this utility and have it "Scan for issues". It will show you all the items which are invalid and/or no longer used. You can select all or just pick out any that are SAP related. It will ask if you want a backup 1st. Then once the items are cleaned up, reinstall the 7.30 version. I have had about a 99% sucess rate using this method over many "odd" GUI errors which could not be determined by other means.
Regards,
Zecher