[Beta 1.7.0.227 not installing]

Rich313's solution worked for me, on Windows 10 4K screen. Thanks!

[please help! "Failed to open file"]

I have encountered this same message & problem in Designer. 

 

The file did have 5 art boards to start, then modified to 3, saved to local hard drive. (Cloud backup every 4 hours, so the backup file is the same)

 

I printed the file for client to approve, make notes, and hadn't opened the file in "about" 2, 2.5 weeks awaiting their feedback.

I cannot remember exactly how I saved it at the time. (cntl+S or through tool bar menu). Probably ctrl+s, coming from Adobe, that is very habitual now.

 

Designer installed on Dell Alienware 17,  Win10 pro 64bit, 32GB RAM, 1.5TB HD, Intel  i7-4900MQ CPU @ 2.80GHz  NVIDIA Geforce GTX 780M 4GB. 

 

I can send the file (253MB) if you are interested in deconstruction.