The copy&paste intermittently failing is usually to do with the vmtoolsd daemon not running (for whatever reason).
I do see that on one of my VMs every now and then and in that case instead of restarting the VM I first kill the vmtoolsd process that runs under my own user and then run a little batch file.
It has this contents:
"C:\Program Files\VMware\VMware Tools\vmtoolsd.exe" -n vmusr
It gets stuck on running.. which is fine (you can kill the stuck dos screen ) there should again be a vmtoolsd process running under your user account.
In my case I always get copy&paste back after that workaround.
I have it setup via a shortcut so that I can just click it.
Not ideal, but better than rebooting the guest.
Wil| Author of Vimalin. The virtual machine Backup app for VMware Desktop Products
| Vimalin : Automated backups for VMware Fusion and VMware Workstation and Player
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