That’s hard to diagnose as nothing is public for a z-addr. I’d rule out any WinZEC GUI issues first by getting the data directly from the underlying zcashd instance. If you can get to the command line and run the zcash-cli command run (from the
C:\Program Files\winzec directory)
zcash-cli.exe z_gettotalbalance and see if those values match
I’d also check the output of
zcash-cli z_listunspent and finally do a rescan. Check out the “Troubleshooting WinZEC” section of the post here for instructions https://medium.com/@_garethtdavies/winzec-tips-tricks-and-troubleshooting-cde242848457
Edit: Also I’d recommend downloading zec-qt-wallet from https://github.com/ZcashFoundation/zec-qt-wallet/releases. Just install it and it’ll use your existing data directory so will just work.