I'm getting a error, "Cannot open Master.ins" when opening Sonar X3 on a Surface Pro 3 I5 updated to Win 10, I even tried restoring to factory win 8.1. Either OS gives me this error. I got it running on a Sony vaio laptop Win 10. I've tried holding shift and shift +cntl when launching but still get the error.

Try running as administrator.

I did. When Installing, launching, everything where's that option. 

I haven't a clue, danhays but would REALLY appreciate a report on how the Surface Pro 3 and SPlat work together once u get things sorted... I've been thinking about it for my mobile daw down the road. 
 
As Cakewalk and Microsoft work close together, I assume it's some weird anomaly... might call/email support 

Copy this and insert into google search... it brings up the exact same issue you are asking about, ... 
 
Microsoft surface pro 3 : Sonar "Cannot open Master.ins"
 
a couple replies, from 2013 said:  
 
FAQ: Common issues, questions, and resolutions. [Updated 9/25/14]
Basic Steam Installation Troubleshooting: 
Many basic installation issues or problems can be resolved with this helpful info -https://support.steampowered.com/kb_article.php?ref=3219-TDFN-7795

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I've Installed SONAR X3, launched the application, and I recieve an Error (Code=1): 
Error Code 1 means registry entries for the game launcher is missing. 

First please review this link with 3rd party software that may interfere with Steam and installing applications through it: https://support.steampowered.com/kb_article.php?ref=9828-SFLZ-9289

Many times the error is resolved when the offending application is disabled or uninstalled in extreme cases, and then by Verifying the SONAR X3 Application Cache.

Right-Click on 'SONAR X3'

Go to Properties

Go to the Local Data tab

Click on 'Verify Application Data'

When this is done re-launch the application.---------------------------------------------------------------------------------------------------------

Installation takes a long time/Installation never completes: 
First please review this link with 3rd party software that may interfere with Steam and installing applications through it: https://support.steampowered.com/kb_article.php?ref=9828-SFLZ-9289

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Some of my Plug-ins don't show up after installation.
Make sure that you have no pending Windows Updates and your computer does not need to be restarted to complete them. After this is finished, verify the Steam Cache for SONAR X3 then launch again.

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"Cannot Open Master.INS" Error on Launch:
This can be corrected by holding down the CONTROL + SHIFT keys on your keyboard when launching SONAR. This should prompt you with a message that says "SONAR X3 will now personalize your user settings...". Make sure to click [OK] to this message.

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