With Primavera P6 version 18, we can easily install the new version 18 and keep the old version (for example version 16) on the same computer.
After download version 18 installation source, click on Setup:
We will uncheck the option “Replace existing version”:
Click Install as usual:
After finish installation, on the Start menu we can see both the new version 18 and the old version 16:
Khuong Do Blog 
Hello Mr. Khuong,
I am using P6 Professional 18. When I imported a MS Project (XML), it was unlucky that It got an error like that:
Type: TDBXError
Event Code: VTRAT-4016-2
Description: TCVirtualTable.RefreshAppend: TASKRSRC: database disk image is malformed
So, I cannot open any projects (poor me)…
Do you have any solutions for this issue?
Thank you and with arm regards!
Mr. ManhHoang
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