Microsoft support of Windows7 officially ended on Jan. 14 2020.
Microsoft no longer provides security update for the vulnerability. So continuing to run Windows7 might cause security risk such as virus , malware, data leakage threat etc.
Additionally, once such windows7 PC is infected , the infected PC might be controlled to attack the other system.
Don't forget to upgrade OS or buy the new PC.
For the PC's belonging to JAIST, EES license is available to install windows 10. Please refer the following link.