I have been searching for a solution to the problem of Affinity Photo 1.8 since Feb. 27 with no luck til now!!!
I cannot take credit for it since I found the solution on another poster Dan C (moderator). I found it, used it, and it worked perfectly, even after closing an reopening the program several times.
I've copied Dan C instructions below and and am really grateful for his help. I am using Win 10 64bit.
Hope it helps others. James
Dan responding ,
Many thanks for your file. This shows me that your System is missing an .msi file from the previous version of Affinity, which is causing the update to fail as it cannot remove the previous version successfully.
We'll need to manually remove the current version of Affinity Photo from your PC before installing the latest version.
Please download the following tool from Microsoft to uninstall the previous version - https://support.microsoft.com/help/17588/windows-fix-problems-that-block-programs-being-installed-or-removed
Once downloaded please run the tool, select Uninstalling and then Affinity Photo from the list of apps shown.
If you can't see Affinity Photo in the list, select the aptly named first option and then paste the following code in and select OK. Depending on which version you most recently had installed, the code will be slightly different but I believe you'll require the first one below:
1.7.3 - {6EE06075-1F8E-4737-B744-B2BB8E2BFE28} (For me, it just showed Affinity)
1.7.2 - {958C8ACD-8C7A-43ED-92D7-B25B263CAFDA}
Once the uninstaller has completed, please visit the following link and download a fresh copy of the latest AP exe, then navigate to the downloaded .exe right-click on the file and select Run as Administrator, this should hopefully install the app for you as expected. (At this point, I restarted my computer before I opened APhoto, James)
https://store.serif.com/update/windows/photo/1/
I hope this helps!