I have installed PyCharm on two PCs, both running Windows 10 x64. On both PCs I have latest Anaconda.
On first PC, when I get notification of the available update, I just click to start update, then the IDE does it all for me, then asks to restart IDE to complete the update process.
On the other PC it always forces me to download complete PyCharm and then to install it from scratch, which is time consuming and very annoying.
I compared settings on both PCs and was unable to find any differences which might be causing this issue. I even uninstalled PyCharm, removed any directories/files which I found to belong to PyCharm, but it did not help.