Even i had the same issue when i extract spring tools 4. Below are the steps i followed to fix the issue
Step 1:
Downloaded Spring Tools 4 bundled jar from
Spring Tools 4 Download
Step 2: Right click downloaded jar and extract using WinZip

Step 3: Now unzip the contents.zip file using WinZip but it throws below error

Step 4: Here use 7Zip to extract contents zip instead of WinZip:
Now it got extracted without any issue.
Step 5: Here we go, open SpringToolSuite4.ini and add below
openFile
-vm
C:/jdk/jdk1.8/bin/javaw
Step 6: Thats it, open SpringToolSuite4.exe
Please note, you may use 7Zip for the steps wherever i mentioned WinZip.
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