I blindly installed/updated the app and several VM's. Particularly the Windows 7 and earlier XP x86 installations had trouble with updates. I spent many hours with three different techs doing investigations as to why my installs were so slow. Most of the answers and fixes involve several different categories. In general, seemingly unknown to me Parallels has an "ideal profile" of installation where the app will work best. Beneath this perfect world scenario, there is the routine or general category (everybody else).
Beyond that, I had a tech work on the my system (the host system) for many hours where they logged into my host computer and did stuff to my installation. During one of the three times that occurred, they caused my (Windows 7) VM to crash so thoroughly as to make system repeatedly crash and never boot (e.g., unusable). That wasn't even the point where they warned me to have a backup handy in case it got messed up. Luckily I have extensive backups.
Be warned, if you work with them on a chat, your VM can be easily screwed up, you can't intervene easily (other than shutting down the computer host and you may be left with an unusable system as happened to me. This caused me countless hours of frustration (I'm being kind here).
My system now works much better with the following recommendations I eventually received from Support in writing (as opposed to their meddling over internet):
HTML:
https://kb.parallels.com/en/112091
I disregarded their recommendations which don't have anything to do with my performance (e.g. their perfect world scenario):
- NEVER run on external drive.
- ALWAYS run on internal (SSD) drive
- ALWAYS run with 128GB Drive allocation
- ALWAYS set your memory partition to 50% of maximum, in increments of 1024B.
Another thing that happened after install and stabilizing the system back to a long time previous version (2016 updates), the updates wouldn't actually occur from that point, and there were so many of them that the time to wait it out was huge. No one at Parallels told me that Microsoft has a roll up of all current updates as a single 300MB file (kind of like a SP2 version for Windows 7 x 86 available). Have a look at KB3125574 at Microsoft Updates on the web or here:
HTML:
https://www.howtogeek.com/255435/how-to-update-windows-7-all-at-once-with-microsofts-convenience-rollup/
.
The last person (kind of a last straw before going on my own) told me he knew of problems in V 13.3.2 and earlier and forced me into 13.0, where I am now and seems stable enough. The issues I had were that the Host app's menu froze plus the VM froze up sue to storage and/or allocated RAM configuration issues. IMO, that should never happen and did in the currently installed version. And that was the last person I spoke with, the other two never mentioned such an issue!
I had these experiences and must rate the overall efficiency and performance of support in these cases @1/10 what it should be. The '1' is trying but not not achieving a repair. 
Last edited: Jul 26, 2018
